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
)

Parameters

left
Type: System.Linq.Expressions.Expression

An Expression to set the Left property equal to.

right
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)),
    Expression.AddAssign(
        variableExpr,
        Expression.Constant(2)
    )
);

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

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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