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CodeDirectionExpression Class

Represents an expression used as a method invoke parameter along with a reference direction indicator.


Namespace:  System.CodeDom
Assembly:  System (in System.dll)

public class CodeDirectionExpression : CodeExpression

The CodeDirectionExpression type exposes the following members.

Public methodCodeDirectionExpression()Initializes a new instance of the CodeDirectionExpression class.
Public methodCodeDirectionExpression(FieldDirection, CodeExpression)Initializes a new instance of the CodeDirectionExpression class using the specified field direction and expression.

Public propertyDirectionGets or sets the field direction for this direction expression.
Public propertyExpressionGets or sets the code expression to represent.
Public propertyUserDataGets the user-definable data for the current object. (Inherited from CodeObject.)

Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

CodeDirectionExpression can represent a parameter passed to a method and the reference direction of the parameter.

The Expression property indicates the expression to qualify with a direction. The Direction property indicates the direction of the parameter using one of the FieldDirection enumeration values.


CodeDirectionExpression is intended to be used as a method invoke parameter, and should not be used when declaring methods.

The following example demonstrates use of a CodeDirectionExpression to specify a field direction modifier for an expression to pass as a method parameter.

// Declares a parameter passed by reference using a CodeDirectionExpression.
CodeDirectionExpression param1 = new CodeDirectionExpression(FieldDirection.Ref, new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "TestParameter" ));
// Invokes a method on this named TestMethod using the direction expression as a parameter.
CodeMethodInvokeExpression methodInvoke1 = new CodeMethodInvokeExpression(new CodeThisReferenceExpression(), "TestMethod", param1 );

// A C# code generator produces the following source code for the preceeding example code:    

//        this.TestMethod(ref TestParameter);

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, 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.

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