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Expression.AddAssign Method (Expression, Expression)

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 static BinaryExpression AddAssign(
	Expression left,
	Expression right


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:
// using System.Linq.Expressions;

// The Parameter expression is used to create a variable.
ParameterExpression variableExpr = Expression.Variable(typeof(int), "sampleVar");

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

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

// 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

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.