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Expression.Empty Method

Definition

Creates an empty expression that has Void type.

public:
 static System::Linq::Expressions::DefaultExpression ^ Empty();
public static System.Linq.Expressions.DefaultExpression Empty ();
static member Empty : unit -> System.Linq.Expressions.DefaultExpression
Public Shared Function Empty () As DefaultExpression

Returns

A DefaultExpression that has the NodeType property equal to Default and the Type property set to Void.

Examples

The following code example shows how to create an empty expression and add it to a block expression.

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

// This statement creates an empty expression.
DefaultExpression emptyExpr = Expression.Empty();

// The empty expression can be used where an expression is expected, but no action is desired.
// For example, you can use the empty expression as the last expression in the block expression.
// In this case the block expression's return value is void.
var emptyBlock = Expression.Block(emptyExpr);
' Add the following directive to your file:
' Imports System.Linq.Expressions 

' This statement creates an empty expression.
Dim emptyExpr As DefaultExpression = Expression.Empty()

' An empty expression can be used where an expression is expected but no action is desired.
' For example, you can use an empty expression as the last expression in a block expression.
' In this case, the block expression's return value is void.
Dim emptyBlock = Expression.Block(emptyExpr)

Remarks

An empty expression can be used where an expression is expected but no action is desired. For example, you can use an empty expression as the last expression in a block expression. In this case, the block expression's return value is void.

Applies to