ILGenerator.BeginScope Methode

Definition

Leitet einen lexikalischen Gültigkeitsbereich ein.

public:
 virtual void BeginScope();
public virtual void BeginScope ();
abstract member BeginScope : unit -> unit
override this.BeginScope : unit -> unit
Public Overridable Sub BeginScope ()

Ausnahmen

Beispiele

Im folgenden Codebeispiel wird die Verwendung von BeginScope und .EndScope

// Get the current AppDomain.
AppDomain^ myAppDomain = AppDomain::CurrentDomain;
AssemblyName^ myAssemblyName = gcnew AssemblyName;
myAssemblyName->Name = "SampleAssembly";

// Create a dynamic assembly 'myAssembly' with access mode 'Run'.
AssemblyBuilder^ myAssembly = myAppDomain->DefineDynamicAssembly( myAssemblyName, AssemblyBuilderAccess::Run );

// Create a dynamic module 'myModule' in 'myAssembly'.
ModuleBuilder^ myModule = myAssembly->DefineDynamicModule( "MyDynamicModule", true );

// Define a public class 'MyDynamicClass'.
TypeBuilder^ myTypeBuilder = myModule->DefineType( "MyDynamicClass", TypeAttributes::Public );

// Define a public string field.
FieldBuilder^ myField = myTypeBuilder->DefineField( "MyDynamicField", String::typeid, FieldAttributes::Public );

// Create the constructor.
array<Type^>^myConstructorArgs = {String::typeid};
ConstructorBuilder^ myConstructor = myTypeBuilder->DefineConstructor( MethodAttributes::Public, CallingConventions::Standard, myConstructorArgs );

// Generate IL for 'myConstructor'.
ILGenerator^ myConstructorIL = myConstructor->GetILGenerator();

// Emit the necessary opcodes.
myConstructorIL->Emit( OpCodes::Ldarg_0 );
ConstructorInfo^ mySuperConstructor = Object::typeid->GetConstructor( gcnew array<Type^>(0) );
myConstructorIL->Emit( OpCodes::Call, mySuperConstructor );
myConstructorIL->Emit( OpCodes::Ldarg_0 );
myConstructorIL->Emit( OpCodes::Ldarg_1 );
myConstructorIL->Emit( OpCodes::Stfld, myField );
myConstructorIL->Emit( OpCodes::Ret );

// Define a dynamic method named 'MyDynamicMethod'.
MethodBuilder^ myMethod = myTypeBuilder->DefineMethod( "MyDynamicMethod", MethodAttributes::Public, String::typeid, nullptr );

// Generate IL for 'myMethod'.
ILGenerator^ myMethodIL = myMethod->GetILGenerator();

// Begin the scope for a local variable.
myMethodIL->BeginScope();
LocalBuilder^ myLocalBuilder = myMethodIL->DeclareLocal( int::typeid );
Console::WriteLine( "\nTrying to access the local variable within the scope." );
Console::WriteLine( "'myLocalBuilder' type is :{0}", myLocalBuilder->LocalType );
myMethodIL->Emit( OpCodes::Ldstr, "Local value" );
myMethodIL->Emit( OpCodes::Stloc_0, myLocalBuilder );

// End the scope of 'myLocalBuilder'.
myMethodIL->EndScope();

// Access the local variable outside the scope.
Console::WriteLine( "\nTrying to access the local variable outside the scope:\n" );
myMethodIL->Emit( OpCodes::Stloc_0, myLocalBuilder );
myMethodIL->Emit( OpCodes::Ldloc_0 );
myMethodIL->Emit( OpCodes::Ret );

// Create 'MyDynamicClass' class.
Type^ myType1 = myTypeBuilder->CreateType();
// Get the current AppDomain.
AppDomain myAppDomain = AppDomain.CurrentDomain;
AssemblyName myAssemblyName = new AssemblyName();
myAssemblyName.Name = "SampleAssembly";

// Create a dynamic assembly 'myAssembly' with access mode 'Run'.
AssemblyBuilder myAssembly = myAppDomain.DefineDynamicAssembly(
                        myAssemblyName, AssemblyBuilderAccess.Run);
// Create a dynamic module 'myModule' in 'myAssembly'.
ModuleBuilder myModule=myAssembly.DefineDynamicModule("MyDynamicModule",true);
// Define a public class 'MyDynamicClass'.
TypeBuilder myTypeBuilder = myModule.DefineType("MyDynamicClass",
                                 TypeAttributes.Public);
// Define a public string field.
FieldBuilder myField = myTypeBuilder.DefineField("MyDynamicField",
                         typeof(String), FieldAttributes.Public);
// Create the constructor.
Type[] myConstructorArgs = {typeof(String)};
ConstructorBuilder myConstructor = myTypeBuilder.DefineConstructor(
   MethodAttributes.Public, CallingConventions.Standard, myConstructorArgs);

// Generate IL for 'myConstructor'.
ILGenerator myConstructorIL = myConstructor.GetILGenerator();
// Emit the necessary opcodes.
myConstructorIL.Emit(OpCodes.Ldarg_0);
ConstructorInfo mySuperConstructor = typeof(Object).GetConstructor(new Type[0]);
myConstructorIL.Emit(OpCodes.Call, mySuperConstructor);
myConstructorIL.Emit(OpCodes.Ldarg_0);
myConstructorIL.Emit(OpCodes.Ldarg_1);
myConstructorIL.Emit(OpCodes.Stfld, myField);
myConstructorIL.Emit(OpCodes.Ret);

// Define a dynamic method named 'MyDynamicMethod'.
MethodBuilder myMethod = myTypeBuilder.DefineMethod("MyDynamicMethod",
   MethodAttributes.Public, typeof(String), null);
// Generate IL for 'myMethod'.
ILGenerator myMethodIL = myMethod.GetILGenerator();

// Begin the scope for a local variable.
myMethodIL.BeginScope();

LocalBuilder myLocalBuilder = myMethodIL.DeclareLocal(typeof(int));
Console.WriteLine("\nTrying to access the local variable within the scope.");
Console.WriteLine("'myLocalBuilder' type is: {0}", myLocalBuilder.LocalType);
myMethodIL.Emit(OpCodes.Ldstr, "Local value");
myMethodIL.Emit(OpCodes.Stloc_0, myLocalBuilder);

// End the scope of 'myLocalBuilder'.
myMethodIL.EndScope();

// Access the local variable outside the scope.
Console.WriteLine("\nTrying to access the local variable outside the scope:");
myMethodIL.Emit(OpCodes.Stloc_0, myLocalBuilder);
myMethodIL.Emit(OpCodes.Ldloc_0 );
myMethodIL.Emit(OpCodes.Ret );

// Create 'MyDynamicClass' class.
Type myType1 = myTypeBuilder.CreateType();
' Get the current AppDomain.
Dim myAppDomain As AppDomain = AppDomain.CurrentDomain
Dim myAssemblyName As New AssemblyName()
myAssemblyName.Name = "SampleAssembly"

' Create a dynamic assembly 'myAssembly' with access mode 'Run'.
Dim myAssembly As AssemblyBuilder = myAppDomain.DefineDynamicAssembly(myAssemblyName, _
                                                            AssemblyBuilderAccess.Run)
' Create a dynamic module 'myModule' in 'myAssembly'.
Dim myModule As ModuleBuilder = myAssembly.DefineDynamicModule("MyDynamicModule", True)
' Define a public class 'MyDynamicClass'.
Dim myTypeBuilder As TypeBuilder = myModule.DefineType("MyDynamicClass", _
                                                               TypeAttributes.Public)
' Define a public string field.
Dim myField As FieldBuilder = myTypeBuilder.DefineField("MyDynamicField", GetType(String), _
                                                               FieldAttributes.Public)
' Create the constructor.
Dim myConstructorArgs As Type() = {GetType(String)}
Dim myConstructor As ConstructorBuilder = myTypeBuilder.DefineConstructor _
               (MethodAttributes.Public, CallingConventions.Standard, myConstructorArgs)

' Generate IL for 'myConstructor'.
Dim myConstructorIL As ILGenerator = myConstructor.GetILGenerator()
' Emit the necessary opcodes.
myConstructorIL.Emit(OpCodes.Ldarg_0)
Dim mySuperConstructor As ConstructorInfo = GetType(Object).GetConstructor(New Type() {})
myConstructorIL.Emit(OpCodes.Call, mySuperConstructor)
myConstructorIL.Emit(OpCodes.Ldarg_0)
myConstructorIL.Emit(OpCodes.Ldarg_1)
myConstructorIL.Emit(OpCodes.Stfld, myField)
myConstructorIL.Emit(OpCodes.Ret)

' Define a dynamic method named 'MyDynamicMethod'.
Dim myMethod As MethodBuilder = myTypeBuilder.DefineMethod("MyDynamicMethod", _
                        MethodAttributes.Public, GetType(String), Nothing)
' Generate IL for 'myMethod'.
Dim myMethodIL As ILGenerator = myMethod.GetILGenerator()

' Begin the scope for a local variable.
myMethodIL.BeginScope()

Dim myLocalBuilder As LocalBuilder = myMethodIL.DeclareLocal(GetType(Integer))
Console.WriteLine(ControlChars.NewLine + "Trying to access the local variable within" + _
                                                                     " the scope.")
Console.WriteLine("'myLocalBuilder' type is: {0}", myLocalBuilder.LocalType)
myMethodIL.Emit(OpCodes.Ldstr, "Local value")
myMethodIL.Emit(OpCodes.Stloc_0, myLocalBuilder)

' End the scope of 'myLocalBuilder'.
myMethodIL.EndScope()

' Access the local variable outside the scope.
Console.WriteLine(ControlChars.NewLine + "Trying to access the local variable outside " + _
                                          "the scope:")
myMethodIL.Emit(OpCodes.Stloc_0, myLocalBuilder)
myMethodIL.Emit(OpCodes.Ldloc_0)
myMethodIL.Emit(OpCodes.Ret)

' Create 'MyDynamicClass' class.
Dim myType1 As Type = myTypeBuilder.CreateType()

Hinweise

Diese Methode wird verwendet, um symbolische Informationen zu senden. Lokale Variablen, die nach BeginScope dem Bereich deklariert wurden, bis die entsprechende EndScope aufgerufen wird.

Wenn der Aktuelle ILGenerator einem DynamicMethod Objekt zugeordnet ist, unterstützt er keine symbolischen Informationen.

Gilt für: