Expression.Block Metode

Definisi

Ruang nama:

System.Linq.Expressions

Rakitan:

System.Linq.Expressions.dll

BlockExpressionMembuat .

Overload

Block(Type, IEnumerable<ParameterExpression>, IEnumerable<Expression>)	Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.
Block(Expression, Expression, Expression)	Membuat yang BlockExpression berisi tiga ekspresi dan tidak memiliki variabel.
Block(Expression, Expression, Expression, Expression, Expression)	BlockExpression Membuat yang berisi lima ekspresi dan tidak memiliki variabel.
Block(Type, IEnumerable<ParameterExpression>, Expression[])	Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.
Block(Type, Expression[])	BlockExpression Membuat yang berisi ekspresi yang diberikan, tidak memiliki variabel dan memiliki jenis hasil tertentu.
Block(Expression, Expression, Expression, Expression)	BlockExpression Membuat yang berisi empat ekspresi dan tidak memiliki variabel.
Block(Expression, Expression)	Membuat yang BlockExpression berisi dua ekspresi dan tidak memiliki variabel.
Block(IEnumerable<ParameterExpression>, Expression[])	Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.
Block(IEnumerable<ParameterExpression>, IEnumerable<Expression>)	Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.
Block(Expression[])	Membuat yang BlockExpression berisi ekspresi yang diberikan dan tidak memiliki variabel.
Block(IEnumerable<Expression>)	Membuat yang BlockExpression berisi ekspresi yang diberikan dan tidak memiliki variabel.
Block(Type, IEnumerable<Expression>)	BlockExpression Membuat yang berisi ekspresi yang diberikan, tidak memiliki variabel dan memiliki jenis hasil tertentu.

Block(Type, IEnumerable<ParameterExpression>, IEnumerable<Expression>)

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(Type ^ type, System::Collections::Generic::IEnumerable<System::Linq::Expressions::ParameterExpression ^> ^ variables, System::Collections::Generic::IEnumerable<System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (Type type, System.Collections.Generic.IEnumerable<System.Linq.Expressions.ParameterExpression>? variables, System.Collections.Generic.IEnumerable<System.Linq.Expressions.Expression> expressions);

static member Block : Type * seq<System.Linq.Expressions.ParameterExpression> * seq<System.Linq.Expressions.Expression> -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (type As Type, variables As IEnumerable(Of ParameterExpression), expressions As IEnumerable(Of Expression)) As BlockExpression

Parameter

type

Type

Jenis hasil blok.

variables

IEnumerable<ParameterExpression>

Variabel di blok .

expressions

IEnumerable<Expression>

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Block(Expression, Expression, Expression)

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi tiga ekspresi dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Linq::Expressions::Expression ^ arg0, System::Linq::Expressions::Expression ^ arg1, System::Linq::Expressions::Expression ^ arg2);

public static System.Linq.Expressions.BlockExpression Block (System.Linq.Expressions.Expression arg0, System.Linq.Expressions.Expression arg1, System.Linq.Expressions.Expression arg2);

static member Block : System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (arg0 As Expression, arg1 As Expression, arg2 As Expression) As BlockExpression

Parameter

arg0

Expression

Ekspresi pertama di blok .

arg1

Expression

Ekspresi kedua di blok .

arg2

Expression

Ekspresi ketiga di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(Expression, Expression, Expression, Expression, Expression)

Sumber:

BlockExpression.cs

BlockExpression Membuat yang berisi lima ekspresi dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Linq::Expressions::Expression ^ arg0, System::Linq::Expressions::Expression ^ arg1, System::Linq::Expressions::Expression ^ arg2, System::Linq::Expressions::Expression ^ arg3, System::Linq::Expressions::Expression ^ arg4);

public static System.Linq.Expressions.BlockExpression Block (System.Linq.Expressions.Expression arg0, System.Linq.Expressions.Expression arg1, System.Linq.Expressions.Expression arg2, System.Linq.Expressions.Expression arg3, System.Linq.Expressions.Expression arg4);

static member Block : System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (arg0 As Expression, arg1 As Expression, arg2 As Expression, arg3 As Expression, arg4 As Expression) As BlockExpression

Parameter

arg0

Expression

Ekspresi pertama di blok .

arg1

Expression

Ekspresi kedua di blok .

arg2

Expression

Ekspresi ketiga di blok .

arg3

Expression

Ekspresi keempat dalam blok .

arg4

Expression

Ekspresi kelima di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(Type, IEnumerable<ParameterExpression>, Expression[])

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(Type ^ type, System::Collections::Generic::IEnumerable<System::Linq::Expressions::ParameterExpression ^> ^ variables, ... cli::array <System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (Type type, System.Collections.Generic.IEnumerable<System.Linq.Expressions.ParameterExpression>? variables, params System.Linq.Expressions.Expression[] expressions);

static member Block : Type * seq<System.Linq.Expressions.ParameterExpression> * System.Linq.Expressions.Expression[] -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (type As Type, variables As IEnumerable(Of ParameterExpression), ParamArray expressions As Expression()) As BlockExpression

Parameter

type

Type

Jenis hasil blok.

variables

IEnumerable<ParameterExpression>

Variabel di blok .

expressions

Expression[]

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Block(Type, Expression[])

Sumber:

BlockExpression.cs

BlockExpression Membuat yang berisi ekspresi yang diberikan, tidak memiliki variabel dan memiliki jenis hasil tertentu.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(Type ^ type, ... cli::array <System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (Type type, params System.Linq.Expressions.Expression[] expressions);

static member Block : Type * System.Linq.Expressions.Expression[] -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (type As Type, ParamArray expressions As Expression()) As BlockExpression

Parameter

type

Type

Jenis hasil blok.

expressions

Expression[]

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Block(Expression, Expression, Expression, Expression)

Sumber:

BlockExpression.cs

BlockExpression Membuat yang berisi empat ekspresi dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Linq::Expressions::Expression ^ arg0, System::Linq::Expressions::Expression ^ arg1, System::Linq::Expressions::Expression ^ arg2, System::Linq::Expressions::Expression ^ arg3);

public static System.Linq.Expressions.BlockExpression Block (System.Linq.Expressions.Expression arg0, System.Linq.Expressions.Expression arg1, System.Linq.Expressions.Expression arg2, System.Linq.Expressions.Expression arg3);

static member Block : System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.Expression -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (arg0 As Expression, arg1 As Expression, arg2 As Expression, arg3 As Expression) As BlockExpression

Parameter

arg0

Expression

Ekspresi pertama di blok .

arg1

Expression

Ekspresi kedua di blok .

arg2

Expression

Ekspresi ketiga di blok .

arg3

Expression

Ekspresi keempat dalam blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(Expression, Expression)

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi dua ekspresi dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Linq::Expressions::Expression ^ arg0, System::Linq::Expressions::Expression ^ arg1);

public static System.Linq.Expressions.BlockExpression Block (System.Linq.Expressions.Expression arg0, System.Linq.Expressions.Expression arg1);

static member Block : System.Linq.Expressions.Expression * System.Linq.Expressions.Expression -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (arg0 As Expression, arg1 As Expression) As BlockExpression

Parameter

arg0

Expression

Ekspresi pertama di blok .

arg1

Expression

Ekspresi kedua di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(IEnumerable<ParameterExpression>, Expression[])

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Collections::Generic::IEnumerable<System::Linq::Expressions::ParameterExpression ^> ^ variables, ... cli::array <System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (System.Collections.Generic.IEnumerable<System.Linq.Expressions.ParameterExpression>? variables, params System.Linq.Expressions.Expression[] expressions);

static member Block : seq<System.Linq.Expressions.ParameterExpression> * System.Linq.Expressions.Expression[] -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (variables As IEnumerable(Of ParameterExpression), ParamArray expressions As Expression()) As BlockExpression

Parameter

variables

IEnumerable<ParameterExpression>

Variabel di blok .

expressions

Expression[]

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(IEnumerable<ParameterExpression>, IEnumerable<Expression>)

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi variabel dan ekspresi yang diberikan.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Collections::Generic::IEnumerable<System::Linq::Expressions::ParameterExpression ^> ^ variables, System::Collections::Generic::IEnumerable<System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (System.Collections.Generic.IEnumerable<System.Linq.Expressions.ParameterExpression>? variables, System.Collections.Generic.IEnumerable<System.Linq.Expressions.Expression> expressions);

static member Block : seq<System.Linq.Expressions.ParameterExpression> * seq<System.Linq.Expressions.Expression> -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (variables As IEnumerable(Of ParameterExpression), expressions As IEnumerable(Of Expression)) As BlockExpression

Parameter

variables

IEnumerable<ParameterExpression>

Variabel di blok .

expressions

IEnumerable<Expression>

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Contoh

Contoh kode berikut menunjukkan cara meneruskan parameter ke ekspresi blok dan memproses parameter ini dalam blok.

// Add the following directive to your file:
// using System.Linq.Expressions;

// This block has a parameter expression
// that represents a variable within the block scope.
// It assigns a value to the variable,
// and then adds a constant to the assigned value.

ParameterExpression varExpr = Expression.Variable(typeof(int), "sampleVar");
BlockExpression blockExpr = Expression.Block(
    new ParameterExpression[] { varExpr },
    Expression.Assign(varExpr, Expression.Constant(1)),
    Expression.Add(varExpr, Expression.Constant(5))
);

// Print out the expressions from the block expression.
Console.WriteLine("The expressions from the block expression:");
foreach (var expr in blockExpr.Expressions)
    Console.WriteLine(expr.ToString());

Console.WriteLine("The result of executing the expression tree:");
// The following statement first creates an expression tree,
// then compiles it, and then executes it.
Console.WriteLine(
    Expression.Lambda<Func<int>>(blockExpr).Compile()());

// This code example produces the following output:
// The expressions from the block expression:
// (sampleVar = 1)
// (sampleVar + 5)
// The result of executing the expression tree:
// 6

' Add the following directive to your file:
' Imports System.Linq.Expressions  


' This block has a parameter expression
' that represents a variable within the block scope.
' It assigns a value to the variable,
' and then adds a constant to the assigned value. 

Dim varExpr As ParameterExpression = Expression.Variable(GetType(Integer), "sampleVar")
Dim blockExpr As BlockExpression = Expression.Block(
    New ParameterExpression() {varExpr},
    Expression.Assign(varExpr, Expression.Constant(1)),
    Expression.Add(varExpr, Expression.Constant(5))
)

' Print the expressions from the block expression.

Console.WriteLine("The expressions from the block expression:")
For Each expr In blockExpr.Expressions
    Console.WriteLine(expr.ToString())
Next

Console.WriteLine("The result of executing the expression tree:")

' The following statement first creates an expression tree,
' then compiles it, and then executes it.
Console.WriteLine(
    Expression.Lambda(Of Func(Of Integer))(blockExpr).Compile()())

' This code example produces the following output:
'
' The expressions from the block expression:
' (sampleVar = 1)
' (sampleVar + 5)
' The result of executing the expression tree:
' 6

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(Expression[])

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi ekspresi yang diberikan dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(... cli::array <System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (params System.Linq.Expressions.Expression[] expressions);

static member Block : System.Linq.Expressions.Expression[] -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (ParamArray expressions As Expression()) As BlockExpression

Parameter

expressions

Expression[]

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Contoh

Contoh kode berikut menunjukkan cara membuat ekspresi blok. Ekspresi blok terdiri dari dua MethodCallExpression objek dan satu ConstantExpression objek.

// Add the following directive to your file:
// using System.Linq.Expressions;

// The block expression allows for executing several expressions sequentually.
// When the block expression is executed,
// it returns the value of the last expression in the sequence.
BlockExpression blockExpr = Expression.Block(
    Expression.Call(
        null,
        typeof(Console).GetMethod("Write", new Type[] { typeof(String) }),
        Expression.Constant("Hello ")
       ),
    Expression.Call(
        null,
        typeof(Console).GetMethod("WriteLine", new Type[] { typeof(String) }),
        Expression.Constant("World!")
        ),
    Expression.Constant(42)
);

Console.WriteLine("The result of executing the expression tree:");
// The following statement first creates an expression tree,
// then compiles it, and then executes it.
var result = Expression.Lambda<Func<int>>(blockExpr).Compile()();

// Print out the expressions from the block expression.
Console.WriteLine("The expressions from the block expression:");
foreach (var expr in blockExpr.Expressions)
    Console.WriteLine(expr.ToString());

// Print out the result of the tree execution.
Console.WriteLine("The return value of the block expression:");
Console.WriteLine(result);

// This code example produces the following output:
//
// The result of executing the expression tree:
// Hello World!

// The expressions from the block expression:
// Write("Hello ")
// WriteLine("World!")
// 42

// The return value of the block expression:
// 42

' Add the following directive to your file:
' Imports System.Linq.Expressions

' The block expression enables you to execute several expressions sequentually.
' When the block expression is executed,
' it returns the value of the last expression in the sequence.
Dim blockExpr As BlockExpression = Expression.Block(
    Expression.Call(
        Nothing,
        GetType(Console).GetMethod("Write", New Type() {GetType(String)}),
        Expression.Constant("Hello ")
       ),
    Expression.Call(
        Nothing,
        GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
        Expression.Constant("World!")
        ),
    Expression.Constant(42)
)

Console.WriteLine("The result of executing the expression tree:")
' The following statement first creates an expression tree,
' then compiles it, and then executes it.           
Dim result = Expression.Lambda(Of Func(Of Integer))(blockExpr).Compile()()

' Print the expressions from the block expression.
Console.WriteLine("The expressions from the block expression:")
For Each expr In blockExpr.Expressions
    Console.WriteLine(expr.ToString())
Next

' Print the result of the tree execution.
Console.WriteLine("The return value of the block expression:")
Console.WriteLine(result)

' This code example produces the following output:
'
' The result of executing the expression tree:
' Hello World!

' The expressions from the block expression:
' Write("Hello ")
' WriteLine("World!")
' 42

' The return value of the block expression:
' 42

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(IEnumerable<Expression>)

Sumber:

BlockExpression.cs

Membuat yang BlockExpression berisi ekspresi yang diberikan dan tidak memiliki variabel.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(System::Collections::Generic::IEnumerable<System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (System.Collections.Generic.IEnumerable<System.Linq.Expressions.Expression> expressions);

static member Block : seq<System.Linq.Expressions.Expression> -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (expressions As IEnumerable(Of Expression)) As BlockExpression

Parameter

expressions

IEnumerable<Expression>

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.

Keterangan

Saat ekspresi blok dijalankan, ekspresi blok mengembalikan nilai ekspresi terakhir di blok .

Block(Type, IEnumerable<Expression>)

Sumber:

BlockExpression.cs

BlockExpression Membuat yang berisi ekspresi yang diberikan, tidak memiliki variabel dan memiliki jenis hasil tertentu.

public:
 static System::Linq::Expressions::BlockExpression ^ Block(Type ^ type, System::Collections::Generic::IEnumerable<System::Linq::Expressions::Expression ^> ^ expressions);

public static System.Linq.Expressions.BlockExpression Block (Type type, System.Collections.Generic.IEnumerable<System.Linq.Expressions.Expression> expressions);

static member Block : Type * seq<System.Linq.Expressions.Expression> -> System.Linq.Expressions.BlockExpression

Public Shared Function Block (type As Type, expressions As IEnumerable(Of Expression)) As BlockExpression

Parameter

type

Type

Jenis hasil blok.

expressions

IEnumerable<Expression>

Ekspresi di blok .

Mengembalikan

BlockExpression

yang dibuat BlockExpression.