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UnaryExpression Class

Represents an expression that has a unary operator.

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.UnaryExpression

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)
public sealed class UnaryExpression : Expression

The UnaryExpression type exposes the following members.

  NameDescription
Public propertyCanReduceGets a value that indicates whether the expression tree node can be reduced. (Overrides Expression.CanReduce.)
Public propertySupported by Portable Class LibraryIsLiftedGets a value that indicates whether the expression tree node represents a lifted call to an operator.
Public propertySupported by Portable Class LibraryIsLiftedToNullGets 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.
Public propertySupported by Portable Class LibraryMethodGets the implementing method for the unary operation.
Public propertyNodeTypeReturns the node type of this Expression. (Overrides Expression.NodeType.)
Public propertySupported by Portable Class LibraryOperandGets the operand of the unary operation.
Public propertyTypeGets the static type of the expression that this Expression represents. (Overrides Expression.Type.)
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  NameDescription
Protected methodAcceptDispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Inherited from Expression.)
Public methodSupported by Portable Class LibraryEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Portable Class LibraryFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Portable Class LibraryGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Portable Class LibraryGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodSupported by Portable Class LibraryMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodReduceReduces the expression node to a simpler expression. (Overrides Expression.Reduce().)
Public methodReduceAndCheckReduces 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.)
Public methodReduceExtensionsReduces 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.)
Public methodSupported by Portable Class LibraryToStringReturns a textual representation of the Expression. (Inherited from Expression.)
Public methodUpdateCreates 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.
Protected methodVisitChildrenReduces 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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The following table summarizes the factory methods that can be used to create a UnaryExpression that has a specific node type.

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

The following example creates a UnaryExpression object that represents the reference conversion of a non-nullable integer expression to the nullable integer type.


// Create a UnaryExpression that represents a
// conversion of an int to an int?.
System.Linq.Expressions.UnaryExpression typeAsExpression =
    System.Linq.Expressions.Expression.TypeAs(
        System.Linq.Expressions.Expression.Constant(34, typeof(int)),
        typeof(int?));

Console.WriteLine(typeAsExpression.ToString());

// This code produces the following output:
//
// (34 As Nullable`1)


.NET Framework

Supported in: 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

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.
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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