Expression.AddAssign Method (Expression, Expression)


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Creates a BinaryExpression that represents an addition assignment operation that does not have overflow checking.

Namespace:   System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)

Public Shared Function AddAssign (
	left As Expression,
	right As Expression
) As BinaryExpression


Type: System.Linq.Expressions.Expression

An Expression to set the Left property equal to.

Type: System.Linq.Expressions.Expression

An Expression to set the Right property equal to.

Return Value

Type: System.Linq.Expressions.BinaryExpression

A BinaryExpression that has the NodeType property equal to AddAssign and the Left and Right properties set to the specified values.

The following code example shows how to create an expression that adds a value to an integer variable and then assigns the result of the operation to the variable.

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

' The parameter expression is used to create a variable.
Dim variableExpr As ParameterExpression = Expression.Variable(GetType(Integer), "sampleVar")

' The block expression enables you to execute several expressions sequentually.
' In this block, the variable is first initialized with 1. 
' Then the AddAssign method adds 2 to the variable and assigns the result to the variable.
Dim addAssignExpr As BlockExpression = Expression.Block(
    New ParameterExpression() {variableExpr},
    Expression.Assign(variableExpr, Expression.Constant(1)),

' Print the expression from the block expression.
Console.WriteLine("The expressions from the block expression:")
For Each expr As Expression In addAssignExpr.Expressions

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))(addAssignExpr).Compile()())

' This code example produces the following output:
' The expressions from the block expression:
' (sampleVar = 1)
' (sampleVar += 2)

' The result of executing the expression tree:
' 3

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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