ILGenerator.Emit Metoda
Definice
Důležité
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Vloží instrukce do datového proudu jazyka MSIL (Microsoft Intermediate Language) pro kompilátor JIT (just-in-time).
Přetížení
Emit(OpCode, LocalBuilder) |
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný indexem dané místní proměnné. |
Emit(OpCode, Type) |
Vloží zadanou instrukce do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný tokenem metadat pro daný typ. |
Emit(OpCode, String) |
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný tokenem metadat pro daný řetězec. |
Emit(OpCode, Single) |
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, SByte) |
Vloží zadaný argument instrukce a znaku do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, MethodInfo) |
Vloží zadanou instrukci do streamu microsoft intermediate language (MSIL) následovaný tokenem metadat pro danou metodu. |
Emit(OpCode, SignatureHelper) |
Vloží zadanou instrukci a token podpisu do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Label[]) |
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) a po dokončení oprav ponechá prostor pro zahrnutí popisku. |
Emit(OpCode, FieldInfo) |
Vloží zadanou instrukci a token metadat pro zadané pole do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, ConstructorInfo) |
Vloží zadanou instrukci a token metadat pro zadaný konstruktor do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Int64) |
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Int32) |
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Int16) |
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Double) |
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode, Byte) |
Vloží zadaný argument instrukce a znaku do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language). |
Emit(OpCode) |
Vloží zadanou instrukce do datového proudu instrukcí. |
Emit(OpCode, Label) |
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) a po dokončení oprav ponechá prostor pro zahrnutí popisku. |
Emit(OpCode, LocalBuilder)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný indexem dané místní proměnné.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::LocalBuilder ^ local);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::LocalBuilder ^ local);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.LocalBuilder local);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.LocalBuilder local);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.LocalBuilder -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.LocalBuilder -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.LocalBuilder -> unit
Public Overridable Sub Emit (opcode As OpCode, local As LocalBuilder)
Public MustOverride Sub Emit (opcode As OpCode, local As LocalBuilder)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- local
- LocalBuilder
Místní proměnná.
Výjimky
Nadřazená metoda parametru local
neodpovídá metodě přidružené k tomuto ILGeneratorparametru .
local
je null
.
opcode
je jednobajtů instrukce a local
představuje místní proměnnou s indexem větším než Byte.MaxValue
.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Type)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukce do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný tokenem metadat pro daný typ.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, Type ^ cls);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, Type ^ cls);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, Type cls);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, Type cls);
abstract member Emit : System.Reflection.Emit.OpCode * Type -> unit
override this.Emit : System.Reflection.Emit.OpCode * Type -> unit
abstract member Emit : System.Reflection.Emit.OpCode * Type -> unit
Public Overridable Sub Emit (opcode As OpCode, cls As Type)
Public MustOverride Sub Emit (opcode As OpCode, cls As Type)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
- cls
- Type
Úloha Type
.
Výjimky
cls
je null
.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
. Umístění cls
je zaznamenáno, aby se token mohl v případě potřeby opravit při uchování modulu do přenosného spustitelného souboru (PE).
Platí pro
Emit(OpCode, String)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) následovaný tokenem metadat pro daný řetězec.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::String ^ str);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::String ^ str);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, string str);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, string str);
abstract member Emit : System.Reflection.Emit.OpCode * string -> unit
override this.Emit : System.Reflection.Emit.OpCode * string -> unit
abstract member Emit : System.Reflection.Emit.OpCode * string -> unit
Public Overridable Sub Emit (opcode As OpCode, str As String)
Public MustOverride Sub Emit (opcode As OpCode, str As String)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- str
- String
Hodnota String
, která se má vygenerovat.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
. Umístění str
souboru se zaznamená pro budoucí opravy, pokud je modul trvale uložen v přenosném spustitelném souboru (PE).
Platí pro
Emit(OpCode, Single)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, float arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, float arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, float arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, float arg);
abstract member Emit : System.Reflection.Emit.OpCode * single -> unit
override this.Emit : System.Reflection.Emit.OpCode * single -> unit
abstract member Emit : System.Reflection.Emit.OpCode * single -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Single)
Public MustOverride Sub Emit (opcode As OpCode, arg As Single)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, SByte)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Důležité
Toto rozhraní API neodpovídá specifikaci CLS.
Vloží zadaný argument instrukce a znaku do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
void Emit(System::Reflection::Emit::OpCode opcode, System::SByte arg);
[System.CLSCompliant(false)]
public void Emit (System.Reflection.Emit.OpCode opcode, sbyte arg);
[<System.CLSCompliant(false)>]
member this.Emit : System.Reflection.Emit.OpCode * sbyte -> unit
Public Sub Emit (opcode As OpCode, arg As SByte)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
- arg
- SByte
Argument znaku nasdílený do datového proudu okamžitě po instrukci.
- Atributy
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, MethodInfo)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci do streamu microsoft intermediate language (MSIL) následovaný tokenem metadat pro danou metodu.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::MethodInfo ^ meth);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::MethodInfo ^ meth);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo meth);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo meth);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo -> unit
Public Overridable Sub Emit (opcode As OpCode, meth As MethodInfo)
Public MustOverride Sub Emit (opcode As OpCode, meth As MethodInfo)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- meth
- MethodInfo
A MethodInfo
představující metodu.
Výjimky
meth
je null
.
meth
je obecná metoda, pro kterou IsGenericMethodDefinition je false
vlastnost .
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Umístění meth
je zaznamenáno tak, aby se instrukční stream mohl v případě potřeby opravit při uchování modulu do přenosného spustitelného souboru (PE).
Pokud meth
představuje obecnou metodu, musí se jednat o definici obecné metody. To znamená, že jeho vlastnost MethodInfo.IsGenericMethodDefinition musí být true
.
Platí pro
Emit(OpCode, SignatureHelper)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a token podpisu do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::SignatureHelper ^ signature);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::SignatureHelper ^ signature);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.SignatureHelper signature);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.SignatureHelper signature);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.SignatureHelper -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.SignatureHelper -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.SignatureHelper -> unit
Public Overridable Sub Emit (opcode As OpCode, signature As SignatureHelper)
Public MustOverride Sub Emit (opcode As OpCode, signature As SignatureHelper)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- signature
- SignatureHelper
Pomocná rutina pro vytvoření tokenu podpisu.
Výjimky
signature
je null
.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Label[])
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) a po dokončení oprav ponechá prostor pro zahrnutí popisku.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, cli::array <System::Reflection::Emit::Label> ^ labels);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, cli::array <System::Reflection::Emit::Label> ^ labels);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.Label[] labels);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.Label[] labels);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label[] -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label[] -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label[] -> unit
Public Overridable Sub Emit (opcode As OpCode, labels As Label())
Public MustOverride Sub Emit (opcode As OpCode, labels As Label())
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- labels
- Label[]
Pole objektů popisků, na které se má větvet z tohoto umístění. Použijí se všechny popisky.
Výjimky
con
je null
. Tato výjimka je v rozhraní .NET Framework 4 nová.
Příklady
Následující ukázka kódu znázorňuje vytvoření dynamické metody s tabulkou jump. Tabulka jump je sestavená pomocí pole Label.
using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ BuildMyType()
{
AppDomain^ myDomain = Thread::GetDomain();
AssemblyName^ myAsmName = gcnew AssemblyName;
myAsmName->Name = "MyDynamicAssembly";
AssemblyBuilder^ myAsmBuilder = myDomain->DefineDynamicAssembly( myAsmName, AssemblyBuilderAccess::Run );
ModuleBuilder^ myModBuilder = myAsmBuilder->DefineDynamicModule( "MyJumpTableDemo" );
TypeBuilder^ myTypeBuilder = myModBuilder->DefineType( "JumpTableDemo", TypeAttributes::Public );
array<Type^>^temp0 = {int::typeid};
MethodBuilder^ myMthdBuilder = myTypeBuilder->DefineMethod( "SwitchMe", static_cast<MethodAttributes>(MethodAttributes::Public | MethodAttributes::Static), String::typeid, temp0 );
ILGenerator^ myIL = myMthdBuilder->GetILGenerator();
Label defaultCase = myIL->DefineLabel();
Label endOfMethod = myIL->DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
array<Label>^jumpTable = gcnew array<Label>(5);
jumpTable[ 0 ] = myIL->DefineLabel();
jumpTable[ 1 ] = myIL->DefineLabel();
jumpTable[ 2 ] = myIL->DefineLabel();
jumpTable[ 3 ] = myIL->DefineLabel();
jumpTable[ 4 ] = myIL->DefineLabel();
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator::Emit calls,
// much as a compiler would.
myIL->Emit( OpCodes::Ldarg_0 );
myIL->Emit( OpCodes::Switch, jumpTable );
// Branch on default case
myIL->Emit( OpCodes::Br_S, defaultCase );
// Case arg0 = 0
myIL->MarkLabel( jumpTable[ 0 ] );
myIL->Emit( OpCodes::Ldstr, "are no bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 1
myIL->MarkLabel( jumpTable[ 1 ] );
myIL->Emit( OpCodes::Ldstr, "is one banana" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 2
myIL->MarkLabel( jumpTable[ 2 ] );
myIL->Emit( OpCodes::Ldstr, "are two bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 3
myIL->MarkLabel( jumpTable[ 3 ] );
myIL->Emit( OpCodes::Ldstr, "are three bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 4
myIL->MarkLabel( jumpTable[ 4 ] );
myIL->Emit( OpCodes::Ldstr, "are four bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Default case
myIL->MarkLabel( defaultCase );
myIL->Emit( OpCodes::Ldstr, "are many bananas" );
myIL->MarkLabel( endOfMethod );
myIL->Emit( OpCodes::Ret );
return myTypeBuilder->CreateType();
}
int main()
{
Type^ myType = BuildMyType();
Console::Write( "Enter an integer between 0 and 5: " );
int theValue = Convert::ToInt32( Console::ReadLine() );
Console::WriteLine( "---" );
Object^ myInstance = Activator::CreateInstance( myType, gcnew array<Object^>(0) );
array<Object^>^temp1 = {theValue};
Console::WriteLine( "Yes, there {0} today!", myType->InvokeMember( "SwitchMe", BindingFlags::InvokeMethod, nullptr, myInstance, temp1 ) );
}
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
class DynamicJumpTableDemo
{
public static Type BuildMyType()
{
AppDomain myDomain = Thread.GetDomain();
AssemblyName myAsmName = new AssemblyName();
myAsmName.Name = "MyDynamicAssembly";
AssemblyBuilder myAsmBuilder = myDomain.DefineDynamicAssembly(
myAsmName,
AssemblyBuilderAccess.Run);
ModuleBuilder myModBuilder = myAsmBuilder.DefineDynamicModule(
"MyJumpTableDemo");
TypeBuilder myTypeBuilder = myModBuilder.DefineType("JumpTableDemo",
TypeAttributes.Public);
MethodBuilder myMthdBuilder = myTypeBuilder.DefineMethod("SwitchMe",
MethodAttributes.Public |
MethodAttributes.Static,
typeof(string),
new Type[] {typeof(int)});
ILGenerator myIL = myMthdBuilder.GetILGenerator();
Label defaultCase = myIL.DefineLabel();
Label endOfMethod = myIL.DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
Label[] jumpTable = new Label[] { myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel() };
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator.Emit calls,
// much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0);
myIL.Emit(OpCodes.Switch, jumpTable);
// Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase);
// Case arg0 = 0
myIL.MarkLabel(jumpTable[0]);
myIL.Emit(OpCodes.Ldstr, "are no bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 1
myIL.MarkLabel(jumpTable[1]);
myIL.Emit(OpCodes.Ldstr, "is one banana");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 2
myIL.MarkLabel(jumpTable[2]);
myIL.Emit(OpCodes.Ldstr, "are two bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 3
myIL.MarkLabel(jumpTable[3]);
myIL.Emit(OpCodes.Ldstr, "are three bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 4
myIL.MarkLabel(jumpTable[4]);
myIL.Emit(OpCodes.Ldstr, "are four bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Default case
myIL.MarkLabel(defaultCase);
myIL.Emit(OpCodes.Ldstr, "are many bananas");
myIL.MarkLabel(endOfMethod);
myIL.Emit(OpCodes.Ret);
return myTypeBuilder.CreateType();
}
public static void Main()
{
Type myType = BuildMyType();
Console.Write("Enter an integer between 0 and 5: ");
int theValue = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("---");
Object myInstance = Activator.CreateInstance(myType, new object[0]);
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe",
BindingFlags.InvokeMethod,
null,
myInstance,
new object[] {theValue}));
}
}
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
_
Class DynamicJumpTableDemo
Public Shared Function BuildMyType() As Type
Dim myDomain As AppDomain = Thread.GetDomain()
Dim myAsmName As New AssemblyName()
myAsmName.Name = "MyDynamicAssembly"
Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
AssemblyBuilderAccess.Run)
Dim myModBuilder As ModuleBuilder = myAsmBuilder.DefineDynamicModule("MyJumpTableDemo")
Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("JumpTableDemo", _
TypeAttributes.Public)
Dim myMthdBuilder As MethodBuilder = myTypeBuilder.DefineMethod("SwitchMe", _
MethodAttributes.Public Or MethodAttributes.Static, _
GetType(String), New Type() {GetType(Integer)})
Dim myIL As ILGenerator = myMthdBuilder.GetILGenerator()
Dim defaultCase As Label = myIL.DefineLabel()
Dim endOfMethod As Label = myIL.DefineLabel()
' We are initializing our jump table. Note that the labels
' will be placed later using the MarkLabel method.
Dim jumpTable() As Label = {myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel()}
' arg0, the number we passed, is pushed onto the stack.
' In this case, due to the design of the code sample,
' the value pushed onto the stack happens to match the
' index of the label (in IL terms, the index of the offset
' in the jump table). If this is not the case, such as
' when switching based on non-integer values, rules for the correspondence
' between the possible case values and each index of the offsets
' must be established outside of the ILGenerator.Emit calls,
' much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0)
myIL.Emit(OpCodes.Switch, jumpTable)
' Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase)
' Case arg0 = 0
myIL.MarkLabel(jumpTable(0))
myIL.Emit(OpCodes.Ldstr, "are no bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 1
myIL.MarkLabel(jumpTable(1))
myIL.Emit(OpCodes.Ldstr, "is one banana")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 2
myIL.MarkLabel(jumpTable(2))
myIL.Emit(OpCodes.Ldstr, "are two bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 3
myIL.MarkLabel(jumpTable(3))
myIL.Emit(OpCodes.Ldstr, "are three bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 4
myIL.MarkLabel(jumpTable(4))
myIL.Emit(OpCodes.Ldstr, "are four bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Default case
myIL.MarkLabel(defaultCase)
myIL.Emit(OpCodes.Ldstr, "are many bananas")
myIL.MarkLabel(endOfMethod)
myIL.Emit(OpCodes.Ret)
Return myTypeBuilder.CreateType()
End Function 'BuildMyType
Public Shared Sub Main()
Dim myType As Type = BuildMyType()
Console.Write("Enter an integer between 0 and 5: ")
Dim theValue As Integer = Convert.ToInt32(Console.ReadLine())
Console.WriteLine("---")
Dim myInstance As [Object] = Activator.CreateInstance(myType, New Object() {})
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe", _
BindingFlags.InvokeMethod, Nothing, _
myInstance, New Object() {theValue}))
End Sub
End Class
Poznámky
Vygeneruje tabulku přepínačů.
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Popisky se vytvářejí pomocí DefineLabel a jejich umístění ve streamu je opraveno pomocí MarkLabel. Při použití jednobajtů instrukce může popisek představovat skok maximálně 127 bajtů podél datového proudu.
opcode
musí představovat instrukce větve. Vzhledem k tomu, že větve jsou relativní instrukce, label
budou během procesu opravy nahrazeny správným posunem větve.
Platí pro
Emit(OpCode, FieldInfo)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a token metadat pro zadané pole do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::FieldInfo ^ field);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::FieldInfo ^ field);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.FieldInfo field);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.FieldInfo field);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.FieldInfo -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.FieldInfo -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.FieldInfo -> unit
Public Overridable Sub Emit (opcode As OpCode, field As FieldInfo)
Public MustOverride Sub Emit (opcode As OpCode, field As FieldInfo)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- field
- FieldInfo
A FieldInfo
představující pole.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
. Umístění field
je zaznamenáno tak, aby se instrukční stream mohl v případě potřeby opravit při uchování modulu do přenosného spustitelného souboru (PE).
Platí pro
Emit(OpCode, ConstructorInfo)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a token metadat pro zadaný konstruktor do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::ConstructorInfo ^ con);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::ConstructorInfo ^ con);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.ConstructorInfo con);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.ConstructorInfo con);
[System.Runtime.InteropServices.ComVisible(true)]
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.ConstructorInfo con);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.ConstructorInfo -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.ConstructorInfo -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.ConstructorInfo -> unit
[<System.Runtime.InteropServices.ComVisible(true)>]
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.ConstructorInfo -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.ConstructorInfo -> unit
Public Overridable Sub Emit (opcode As OpCode, con As ConstructorInfo)
Public MustOverride Sub Emit (opcode As OpCode, con As ConstructorInfo)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- con
- ConstructorInfo
A ConstructorInfo
představující konstruktor.
- Atributy
Výjimky
con
je null
. Tato výjimka je v rozhraní .NET Framework 4 nová.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Umístění con
je zaznamenáno tak, aby se instrukční stream mohl v případě potřeby opravit při uchování modulu do přenosného spustitelného souboru (PE).
Platí pro
Emit(OpCode, Int64)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, long arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, long arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, long arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, long arg);
abstract member Emit : System.Reflection.Emit.OpCode * int64 -> unit
override this.Emit : System.Reflection.Emit.OpCode * int64 -> unit
abstract member Emit : System.Reflection.Emit.OpCode * int64 -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Long)
Public MustOverride Sub Emit (opcode As OpCode, arg As Long)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
- arg
- Int64
Číselný argument se do streamu vložil hned po instrukci.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Int32)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, int arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, int arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, int arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, int arg);
abstract member Emit : System.Reflection.Emit.OpCode * int -> unit
override this.Emit : System.Reflection.Emit.OpCode * int -> unit
abstract member Emit : System.Reflection.Emit.OpCode * int -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Integer)
Public MustOverride Sub Emit (opcode As OpCode, arg As Integer)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
- arg
- Int32
Číselný argument se do streamu vložil hned po instrukci.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Int16)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, short arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, short arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, short arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, short arg);
abstract member Emit : System.Reflection.Emit.OpCode * int16 -> unit
override this.Emit : System.Reflection.Emit.OpCode * int16 -> unit
abstract member Emit : System.Reflection.Emit.OpCode * int16 -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Short)
Public MustOverride Sub Emit (opcode As OpCode, arg As Short)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- arg
- Int16
Argument Int
vložený do streamu okamžitě po instrukci.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Double)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci a číselný argument do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, double arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, double arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, double arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, double arg);
abstract member Emit : System.Reflection.Emit.OpCode * double -> unit
override this.Emit : System.Reflection.Emit.OpCode * double -> unit
abstract member Emit : System.Reflection.Emit.OpCode * double -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Double)
Public MustOverride Sub Emit (opcode As OpCode, arg As Double)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu. Definováno ve výčtu OpCodes
.
- arg
- Double
Číselný argument se do streamu vložil hned po instrukci.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode, Byte)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadaný argument instrukce a znaku do datového proudu instrukcí jazyka MSIL (Microsoft Intermediate Language).
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Byte arg);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Byte arg);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, byte arg);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, byte arg);
abstract member Emit : System.Reflection.Emit.OpCode * byte -> unit
override this.Emit : System.Reflection.Emit.OpCode * byte -> unit
abstract member Emit : System.Reflection.Emit.OpCode * byte -> unit
Public Overridable Sub Emit (opcode As OpCode, arg As Byte)
Public MustOverride Sub Emit (opcode As OpCode, arg As Byte)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL, která se má vložit do datového proudu.
- arg
- Byte
Argument znaku nasdílený do datového proudu okamžitě po instrukci.
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Platí pro
Emit(OpCode)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukce do datového proudu instrukcí.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode);
public virtual void Emit (System.Reflection.Emit.OpCode opcode);
public abstract void Emit (System.Reflection.Emit.OpCode opcode);
abstract member Emit : System.Reflection.Emit.OpCode -> unit
override this.Emit : System.Reflection.Emit.OpCode -> unit
abstract member Emit : System.Reflection.Emit.OpCode -> unit
Public Overridable Sub Emit (opcode As OpCode)
Public MustOverride Sub Emit (opcode As OpCode)
Parametry
- opcode
- OpCode
Instrukce jazyka MSIL (Microsoft Intermediate Language), které se mají vložit do datového proudu.
Příklady
Následující ukázka kódu ukazuje použití nástroje k vygenerování výstupu Emit
jazyka MSIL prostřednictvím instance nástroje ILGenerator.
using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ BuildMyType()
{
AppDomain^ myDomain = Thread::GetDomain();
AssemblyName^ myAsmName = gcnew AssemblyName;
myAsmName->Name = "MyDynamicAssembly";
AssemblyBuilder^ myAsmBuilder = myDomain->DefineDynamicAssembly( myAsmName, AssemblyBuilderAccess::Run );
ModuleBuilder^ myModBuilder = myAsmBuilder->DefineDynamicModule( "MyJumpTableDemo" );
TypeBuilder^ myTypeBuilder = myModBuilder->DefineType( "JumpTableDemo", TypeAttributes::Public );
array<Type^>^temp0 = {int::typeid};
MethodBuilder^ myMthdBuilder = myTypeBuilder->DefineMethod( "SwitchMe", static_cast<MethodAttributes>(MethodAttributes::Public | MethodAttributes::Static), String::typeid, temp0 );
ILGenerator^ myIL = myMthdBuilder->GetILGenerator();
Label defaultCase = myIL->DefineLabel();
Label endOfMethod = myIL->DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
array<Label>^jumpTable = gcnew array<Label>(5);
jumpTable[ 0 ] = myIL->DefineLabel();
jumpTable[ 1 ] = myIL->DefineLabel();
jumpTable[ 2 ] = myIL->DefineLabel();
jumpTable[ 3 ] = myIL->DefineLabel();
jumpTable[ 4 ] = myIL->DefineLabel();
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator::Emit calls,
// much as a compiler would.
myIL->Emit( OpCodes::Ldarg_0 );
myIL->Emit( OpCodes::Switch, jumpTable );
// Branch on default case
myIL->Emit( OpCodes::Br_S, defaultCase );
// Case arg0 = 0
myIL->MarkLabel( jumpTable[ 0 ] );
myIL->Emit( OpCodes::Ldstr, "are no bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 1
myIL->MarkLabel( jumpTable[ 1 ] );
myIL->Emit( OpCodes::Ldstr, "is one banana" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 2
myIL->MarkLabel( jumpTable[ 2 ] );
myIL->Emit( OpCodes::Ldstr, "are two bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 3
myIL->MarkLabel( jumpTable[ 3 ] );
myIL->Emit( OpCodes::Ldstr, "are three bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 4
myIL->MarkLabel( jumpTable[ 4 ] );
myIL->Emit( OpCodes::Ldstr, "are four bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Default case
myIL->MarkLabel( defaultCase );
myIL->Emit( OpCodes::Ldstr, "are many bananas" );
myIL->MarkLabel( endOfMethod );
myIL->Emit( OpCodes::Ret );
return myTypeBuilder->CreateType();
}
int main()
{
Type^ myType = BuildMyType();
Console::Write( "Enter an integer between 0 and 5: " );
int theValue = Convert::ToInt32( Console::ReadLine() );
Console::WriteLine( "---" );
Object^ myInstance = Activator::CreateInstance( myType, gcnew array<Object^>(0) );
array<Object^>^temp1 = {theValue};
Console::WriteLine( "Yes, there {0} today!", myType->InvokeMember( "SwitchMe", BindingFlags::InvokeMethod, nullptr, myInstance, temp1 ) );
}
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
class DynamicJumpTableDemo
{
public static Type BuildMyType()
{
AppDomain myDomain = Thread.GetDomain();
AssemblyName myAsmName = new AssemblyName();
myAsmName.Name = "MyDynamicAssembly";
AssemblyBuilder myAsmBuilder = myDomain.DefineDynamicAssembly(
myAsmName,
AssemblyBuilderAccess.Run);
ModuleBuilder myModBuilder = myAsmBuilder.DefineDynamicModule(
"MyJumpTableDemo");
TypeBuilder myTypeBuilder = myModBuilder.DefineType("JumpTableDemo",
TypeAttributes.Public);
MethodBuilder myMthdBuilder = myTypeBuilder.DefineMethod("SwitchMe",
MethodAttributes.Public |
MethodAttributes.Static,
typeof(string),
new Type[] {typeof(int)});
ILGenerator myIL = myMthdBuilder.GetILGenerator();
Label defaultCase = myIL.DefineLabel();
Label endOfMethod = myIL.DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
Label[] jumpTable = new Label[] { myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel() };
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator.Emit calls,
// much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0);
myIL.Emit(OpCodes.Switch, jumpTable);
// Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase);
// Case arg0 = 0
myIL.MarkLabel(jumpTable[0]);
myIL.Emit(OpCodes.Ldstr, "are no bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 1
myIL.MarkLabel(jumpTable[1]);
myIL.Emit(OpCodes.Ldstr, "is one banana");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 2
myIL.MarkLabel(jumpTable[2]);
myIL.Emit(OpCodes.Ldstr, "are two bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 3
myIL.MarkLabel(jumpTable[3]);
myIL.Emit(OpCodes.Ldstr, "are three bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 4
myIL.MarkLabel(jumpTable[4]);
myIL.Emit(OpCodes.Ldstr, "are four bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Default case
myIL.MarkLabel(defaultCase);
myIL.Emit(OpCodes.Ldstr, "are many bananas");
myIL.MarkLabel(endOfMethod);
myIL.Emit(OpCodes.Ret);
return myTypeBuilder.CreateType();
}
public static void Main()
{
Type myType = BuildMyType();
Console.Write("Enter an integer between 0 and 5: ");
int theValue = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("---");
Object myInstance = Activator.CreateInstance(myType, new object[0]);
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe",
BindingFlags.InvokeMethod,
null,
myInstance,
new object[] {theValue}));
}
}
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
_
Class DynamicJumpTableDemo
Public Shared Function BuildMyType() As Type
Dim myDomain As AppDomain = Thread.GetDomain()
Dim myAsmName As New AssemblyName()
myAsmName.Name = "MyDynamicAssembly"
Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
AssemblyBuilderAccess.Run)
Dim myModBuilder As ModuleBuilder = myAsmBuilder.DefineDynamicModule("MyJumpTableDemo")
Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("JumpTableDemo", _
TypeAttributes.Public)
Dim myMthdBuilder As MethodBuilder = myTypeBuilder.DefineMethod("SwitchMe", _
MethodAttributes.Public Or MethodAttributes.Static, _
GetType(String), New Type() {GetType(Integer)})
Dim myIL As ILGenerator = myMthdBuilder.GetILGenerator()
Dim defaultCase As Label = myIL.DefineLabel()
Dim endOfMethod As Label = myIL.DefineLabel()
' We are initializing our jump table. Note that the labels
' will be placed later using the MarkLabel method.
Dim jumpTable() As Label = {myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel()}
' arg0, the number we passed, is pushed onto the stack.
' In this case, due to the design of the code sample,
' the value pushed onto the stack happens to match the
' index of the label (in IL terms, the index of the offset
' in the jump table). If this is not the case, such as
' when switching based on non-integer values, rules for the correspondence
' between the possible case values and each index of the offsets
' must be established outside of the ILGenerator.Emit calls,
' much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0)
myIL.Emit(OpCodes.Switch, jumpTable)
' Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase)
' Case arg0 = 0
myIL.MarkLabel(jumpTable(0))
myIL.Emit(OpCodes.Ldstr, "are no bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 1
myIL.MarkLabel(jumpTable(1))
myIL.Emit(OpCodes.Ldstr, "is one banana")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 2
myIL.MarkLabel(jumpTable(2))
myIL.Emit(OpCodes.Ldstr, "are two bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 3
myIL.MarkLabel(jumpTable(3))
myIL.Emit(OpCodes.Ldstr, "are three bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 4
myIL.MarkLabel(jumpTable(4))
myIL.Emit(OpCodes.Ldstr, "are four bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Default case
myIL.MarkLabel(defaultCase)
myIL.Emit(OpCodes.Ldstr, "are many bananas")
myIL.MarkLabel(endOfMethod)
myIL.Emit(OpCodes.Ret)
Return myTypeBuilder.CreateType()
End Function 'BuildMyType
Public Shared Sub Main()
Dim myType As Type = BuildMyType()
Console.Write("Enter an integer between 0 and 5: ")
Dim theValue As Integer = Convert.ToInt32(Console.ReadLine())
Console.WriteLine("---")
Dim myInstance As [Object] = Activator.CreateInstance(myType, New Object() {})
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe", _
BindingFlags.InvokeMethod, Nothing, _
myInstance, New Object() {theValue}))
End Sub
End Class
Poznámky
opcode
Pokud parametr vyžaduje argument, volající musí zajistit, aby délka argumentu odpovídala délce deklarovaného parametru. V opačném případě budou výsledky nepředvídatelné. Pokud například instrukce Emit vyžaduje 2 bajtový operand a volající poskytne 4 bajtový operand, modul runtime vygeneruje dva další bajty do instrukčního streamu. Tyto nadbytečné bajty budou Nop pokyny.
Instrukční hodnoty jsou definovány v OpCodessouboru .
Platí pro
Emit(OpCode, Label)
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
- Zdroj:
- ILGenerator.cs
Vloží zadanou instrukci do datového proudu jazyka MSIL (Microsoft Intermediate Language) a po dokončení oprav ponechá prostor pro zahrnutí popisku.
public:
virtual void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::Label label);
public:
abstract void Emit(System::Reflection::Emit::OpCode opcode, System::Reflection::Emit::Label label);
public virtual void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.Label label);
public abstract void Emit (System.Reflection.Emit.OpCode opcode, System.Reflection.Emit.Label label);
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label -> unit
override this.Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label -> unit
abstract member Emit : System.Reflection.Emit.OpCode * System.Reflection.Emit.Label -> unit
Public Overridable Sub Emit (opcode As OpCode, label As Label)
Public MustOverride Sub Emit (opcode As OpCode, label As Label)
Parametry
- opcode
- OpCode
Instrukce MSIL, která se má vysílat do datového proudu.
- label
- Label
Popisek, na který se má větev z tohoto umístění.
Příklady
Následující ukázka kódu znázorňuje vytvoření dynamické metody s tabulkou jump. Tabulka jump je sestavená pomocí pole Label.
using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ BuildMyType()
{
AppDomain^ myDomain = Thread::GetDomain();
AssemblyName^ myAsmName = gcnew AssemblyName;
myAsmName->Name = "MyDynamicAssembly";
AssemblyBuilder^ myAsmBuilder = myDomain->DefineDynamicAssembly( myAsmName, AssemblyBuilderAccess::Run );
ModuleBuilder^ myModBuilder = myAsmBuilder->DefineDynamicModule( "MyJumpTableDemo" );
TypeBuilder^ myTypeBuilder = myModBuilder->DefineType( "JumpTableDemo", TypeAttributes::Public );
array<Type^>^temp0 = {int::typeid};
MethodBuilder^ myMthdBuilder = myTypeBuilder->DefineMethod( "SwitchMe", static_cast<MethodAttributes>(MethodAttributes::Public | MethodAttributes::Static), String::typeid, temp0 );
ILGenerator^ myIL = myMthdBuilder->GetILGenerator();
Label defaultCase = myIL->DefineLabel();
Label endOfMethod = myIL->DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
array<Label>^jumpTable = gcnew array<Label>(5);
jumpTable[ 0 ] = myIL->DefineLabel();
jumpTable[ 1 ] = myIL->DefineLabel();
jumpTable[ 2 ] = myIL->DefineLabel();
jumpTable[ 3 ] = myIL->DefineLabel();
jumpTable[ 4 ] = myIL->DefineLabel();
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator::Emit calls,
// much as a compiler would.
myIL->Emit( OpCodes::Ldarg_0 );
myIL->Emit( OpCodes::Switch, jumpTable );
// Branch on default case
myIL->Emit( OpCodes::Br_S, defaultCase );
// Case arg0 = 0
myIL->MarkLabel( jumpTable[ 0 ] );
myIL->Emit( OpCodes::Ldstr, "are no bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 1
myIL->MarkLabel( jumpTable[ 1 ] );
myIL->Emit( OpCodes::Ldstr, "is one banana" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 2
myIL->MarkLabel( jumpTable[ 2 ] );
myIL->Emit( OpCodes::Ldstr, "are two bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 3
myIL->MarkLabel( jumpTable[ 3 ] );
myIL->Emit( OpCodes::Ldstr, "are three bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Case arg0 = 4
myIL->MarkLabel( jumpTable[ 4 ] );
myIL->Emit( OpCodes::Ldstr, "are four bananas" );
myIL->Emit( OpCodes::Br_S, endOfMethod );
// Default case
myIL->MarkLabel( defaultCase );
myIL->Emit( OpCodes::Ldstr, "are many bananas" );
myIL->MarkLabel( endOfMethod );
myIL->Emit( OpCodes::Ret );
return myTypeBuilder->CreateType();
}
int main()
{
Type^ myType = BuildMyType();
Console::Write( "Enter an integer between 0 and 5: " );
int theValue = Convert::ToInt32( Console::ReadLine() );
Console::WriteLine( "---" );
Object^ myInstance = Activator::CreateInstance( myType, gcnew array<Object^>(0) );
array<Object^>^temp1 = {theValue};
Console::WriteLine( "Yes, there {0} today!", myType->InvokeMember( "SwitchMe", BindingFlags::InvokeMethod, nullptr, myInstance, temp1 ) );
}
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
class DynamicJumpTableDemo
{
public static Type BuildMyType()
{
AppDomain myDomain = Thread.GetDomain();
AssemblyName myAsmName = new AssemblyName();
myAsmName.Name = "MyDynamicAssembly";
AssemblyBuilder myAsmBuilder = myDomain.DefineDynamicAssembly(
myAsmName,
AssemblyBuilderAccess.Run);
ModuleBuilder myModBuilder = myAsmBuilder.DefineDynamicModule(
"MyJumpTableDemo");
TypeBuilder myTypeBuilder = myModBuilder.DefineType("JumpTableDemo",
TypeAttributes.Public);
MethodBuilder myMthdBuilder = myTypeBuilder.DefineMethod("SwitchMe",
MethodAttributes.Public |
MethodAttributes.Static,
typeof(string),
new Type[] {typeof(int)});
ILGenerator myIL = myMthdBuilder.GetILGenerator();
Label defaultCase = myIL.DefineLabel();
Label endOfMethod = myIL.DefineLabel();
// We are initializing our jump table. Note that the labels
// will be placed later using the MarkLabel method.
Label[] jumpTable = new Label[] { myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel(),
myIL.DefineLabel() };
// arg0, the number we passed, is pushed onto the stack.
// In this case, due to the design of the code sample,
// the value pushed onto the stack happens to match the
// index of the label (in IL terms, the index of the offset
// in the jump table). If this is not the case, such as
// when switching based on non-integer values, rules for the correspondence
// between the possible case values and each index of the offsets
// must be established outside of the ILGenerator.Emit calls,
// much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0);
myIL.Emit(OpCodes.Switch, jumpTable);
// Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase);
// Case arg0 = 0
myIL.MarkLabel(jumpTable[0]);
myIL.Emit(OpCodes.Ldstr, "are no bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 1
myIL.MarkLabel(jumpTable[1]);
myIL.Emit(OpCodes.Ldstr, "is one banana");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 2
myIL.MarkLabel(jumpTable[2]);
myIL.Emit(OpCodes.Ldstr, "are two bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 3
myIL.MarkLabel(jumpTable[3]);
myIL.Emit(OpCodes.Ldstr, "are three bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Case arg0 = 4
myIL.MarkLabel(jumpTable[4]);
myIL.Emit(OpCodes.Ldstr, "are four bananas");
myIL.Emit(OpCodes.Br_S, endOfMethod);
// Default case
myIL.MarkLabel(defaultCase);
myIL.Emit(OpCodes.Ldstr, "are many bananas");
myIL.MarkLabel(endOfMethod);
myIL.Emit(OpCodes.Ret);
return myTypeBuilder.CreateType();
}
public static void Main()
{
Type myType = BuildMyType();
Console.Write("Enter an integer between 0 and 5: ");
int theValue = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("---");
Object myInstance = Activator.CreateInstance(myType, new object[0]);
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe",
BindingFlags.InvokeMethod,
null,
myInstance,
new object[] {theValue}));
}
}
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
_
Class DynamicJumpTableDemo
Public Shared Function BuildMyType() As Type
Dim myDomain As AppDomain = Thread.GetDomain()
Dim myAsmName As New AssemblyName()
myAsmName.Name = "MyDynamicAssembly"
Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
AssemblyBuilderAccess.Run)
Dim myModBuilder As ModuleBuilder = myAsmBuilder.DefineDynamicModule("MyJumpTableDemo")
Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("JumpTableDemo", _
TypeAttributes.Public)
Dim myMthdBuilder As MethodBuilder = myTypeBuilder.DefineMethod("SwitchMe", _
MethodAttributes.Public Or MethodAttributes.Static, _
GetType(String), New Type() {GetType(Integer)})
Dim myIL As ILGenerator = myMthdBuilder.GetILGenerator()
Dim defaultCase As Label = myIL.DefineLabel()
Dim endOfMethod As Label = myIL.DefineLabel()
' We are initializing our jump table. Note that the labels
' will be placed later using the MarkLabel method.
Dim jumpTable() As Label = {myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel(), _
myIL.DefineLabel()}
' arg0, the number we passed, is pushed onto the stack.
' In this case, due to the design of the code sample,
' the value pushed onto the stack happens to match the
' index of the label (in IL terms, the index of the offset
' in the jump table). If this is not the case, such as
' when switching based on non-integer values, rules for the correspondence
' between the possible case values and each index of the offsets
' must be established outside of the ILGenerator.Emit calls,
' much as a compiler would.
myIL.Emit(OpCodes.Ldarg_0)
myIL.Emit(OpCodes.Switch, jumpTable)
' Branch on default case
myIL.Emit(OpCodes.Br_S, defaultCase)
' Case arg0 = 0
myIL.MarkLabel(jumpTable(0))
myIL.Emit(OpCodes.Ldstr, "are no bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 1
myIL.MarkLabel(jumpTable(1))
myIL.Emit(OpCodes.Ldstr, "is one banana")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 2
myIL.MarkLabel(jumpTable(2))
myIL.Emit(OpCodes.Ldstr, "are two bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 3
myIL.MarkLabel(jumpTable(3))
myIL.Emit(OpCodes.Ldstr, "are three bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Case arg0 = 4
myIL.MarkLabel(jumpTable(4))
myIL.Emit(OpCodes.Ldstr, "are four bananas")
myIL.Emit(OpCodes.Br_S, endOfMethod)
' Default case
myIL.MarkLabel(defaultCase)
myIL.Emit(OpCodes.Ldstr, "are many bananas")
myIL.MarkLabel(endOfMethod)
myIL.Emit(OpCodes.Ret)
Return myTypeBuilder.CreateType()
End Function 'BuildMyType
Public Shared Sub Main()
Dim myType As Type = BuildMyType()
Console.Write("Enter an integer between 0 and 5: ")
Dim theValue As Integer = Convert.ToInt32(Console.ReadLine())
Console.WriteLine("---")
Dim myInstance As [Object] = Activator.CreateInstance(myType, New Object() {})
Console.WriteLine("Yes, there {0} today!", myType.InvokeMember("SwitchMe", _
BindingFlags.InvokeMethod, Nothing, _
myInstance, New Object() {theValue}))
End Sub
End Class
Poznámky
Hodnoty instrukce jsou definovány ve výčtu OpCodes
.
Popisky se vytvářejí pomocí DefineLabela jejich umístění v rámci streamu je opraveno pomocí MarkLabel. Při použití jednobajtů instrukce může popisek představovat skok maximálně 127 bajtů podél datového proudu.
opcode
musí představovat instrukce větve. Vzhledem k tomu, že větve jsou relativní instrukce, label
budou během procesu opravy nahrazeny správným posunem větve.