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11/18/2011

BinaryExpression Class

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Represents an expression that has a binary operator.

Inheritance Hierarchy

System.Object
System.Linq.Expressions.Expression
System.Linq.Expressions.BinaryExpression

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

Syntax

'Declaration
Public Class BinaryExpression _
    Inherits Expression

public class BinaryExpression : Expression

The BinaryExpression type exposes the following members.

Properties

	Name	Description
	CanReduce	Gets a value that indicates whether the expression tree node can be reduced. (Overrides Expression.CanReduce.)
	Conversion	Gets the type conversion function that is used by a coalescing or compound assignment operation.
	IsLifted	Gets a value that indicates whether the expression tree node represents a lifted call to an operator.
	IsLiftedToNull	Gets a value that indicates whether the expression tree node represents a lifted call to an operator whose return type is lifted to a nullable type.
	Left	Gets the left operand of the binary operation.
	Method	Gets the implementing method for the binary operation.
	NodeType	Gets the node type of this Expression. (Inherited from Expression.)
	Right	Gets the right operand of the binary operation.
	Type	Gets the static type of the expression that this Expression represents. (Inherited from Expression.)

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Methods

	Name	Description
	Accept	Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Overrides Expression.Accept(ExpressionVisitor).)
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	Reduce	Reduces the binary expression node to a simpler expression. (Overrides Expression.Reduce().)
	ReduceAndCheck	Reduces this node to a simpler expression. If CanReduce returns true, this should return a valid expression. This method can return another node which itself must be reduced. (Inherited from Expression.)
	ReduceExtensions	Reduces the expression to a known node type (that is not an Extension node) or just returns the expression if it is already a known type. (Inherited from Expression.)
	ToString	Returns a textual representation of the Expression. (Inherited from Expression.)
	Update	Creates a new expression that is like this one, but using the supplied children. If all of the children are the same, it will return this expression.
	VisitChildren	Reduces the node and then calls the visitor delegate on the reduced expression. The method throws an exception if the node is not reducible. (Inherited from Expression.)

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Remarks

The following tables summarize the factory methods that can be used to create a BinaryExpression that has a specific node type, represented by the NodeType property. Each table contains information for a specific class of operations such as arithmetic or bitwise.

Binary Arithmetic Operations

Node Type	Factory Method
Add	Add
AddChecked	AddChecked
Divide	Divide
Modulo	Modulo
Multiply	Multiply
MultiplyChecked	MultiplyChecked
Power	Power
Subtract	Subtract
SubtractChecked	SubtractChecked

Bitwise Operations

Node Type	Factory Method
And	And
Or	Or
ExclusiveOr	ExclusiveOr

Shift Operations

Node Type	Factory Method
LeftShift	LeftShift
RightShift	RightShift

Conditional Boolean Operations

Node Type	Factory Method
AndAlso	AndAlso
OrElse	OrElse

Comparison Operations

Node Type	Factory Method
Equal	Equal
NotEqual	NotEqual
GreaterThanOrEqual	GreaterThanOrEqual
GreaterThan	GreaterThan
LessThan	LessThan
LessThanOrEqual	LessThanOrEqual

Coalescing Operations

Node Type	Factory Method
Coalesce	Coalesce

Array Indexing Operations

Node Type	Factory Method
ArrayIndex	ArrayIndex

In addition, the MakeBinary methods can also be used to create a BinaryExpression. These factory methods can be used to create a BinaryExpression of any node type that represents a binary operation. The parameter of these methods that is of type NodeType specifies the desired node type.

Examples

The following example creates a BinaryExpression object that represents the subtraction of one number from another.

' Create a BinaryExpression that represents subtracting 14 from 53.
Dim binaryExpression As System.Linq.Expressions.BinaryExpression = _
    System.Linq.Expressions.Expression.MakeBinary( _
        System.Linq.Expressions.ExpressionType.Subtract, _
        System.Linq.Expressions.Expression.Constant(53), _
        System.Linq.Expressions.Expression.Constant(14))

outputBlock.Text &= binaryExpression.ToString() & vbCrLf

' This code produces the following output:
'
' (53 - 14)

// Create a BinaryExpression that represents subtracting 14 from 53.
System.Linq.Expressions.BinaryExpression binaryExpression =
    System.Linq.Expressions.Expression.MakeBinary(
        System.Linq.Expressions.ExpressionType.Subtract,
        System.Linq.Expressions.Expression.Constant(53),
        System.Linq.Expressions.Expression.Constant(14));

outputBlock.Text += binaryExpression.ToString() + "\n";

// This code produces the following output:
//
// (53 - 14)

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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