NewExpression Class

Represents a constructor call.

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.NewExpression

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

public class NewExpression : Expression

The NewExpression type exposes the following members.

  NameDescription
Public propertySupported by Portable Class LibraryArgumentsGets the arguments to the constructor.
Public propertySupported by Portable Class LibraryCanReduceIndicates that the node can be reduced to a simpler node. If this returns true, Reduce() can be called to produce the reduced form. (Inherited from Expression.)
Public propertySupported by Portable Class LibraryConstructorGets the called constructor.
Public propertySupported by Portable Class LibraryMembersGets the members that can retrieve the values of the fields that were initialized with constructor arguments.
Public propertySupported by Portable Class LibraryNodeTypeReturns the node type of this Expression. (Overrides Expression.NodeType.)
Public propertySupported by Portable Class LibraryTypeGets the static type of the expression that this Expression represents. (Overrides Expression.Type.)
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  NameDescription
Protected methodSupported by Portable Class LibraryAcceptDispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Overrides Expression.Accept(ExpressionVisitor).)
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 the default hash function. (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 methodSupported by Portable Class LibraryReduceReduces 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 methodSupported by Portable Class LibraryReduceAndCheckReduces 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 methodSupported by Portable Class LibraryReduceExtensionsReduces 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 methodSupported by Portable Class LibraryUpdateCreates 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 methodSupported by Portable Class LibraryVisitChildrenReduces 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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Use the New factory methods to create a NewExpression.

The value of the NodeType property of a NewExpression object is New.

The following example creates a NewExpression that represents the construction of a new instance of a dictionary object.

// Create a NewExpression that represents constructing 
// a new instance of Dictionary<int, string>.
System.Linq.Expressions.NewExpression newDictionaryExpression =
    System.Linq.Expressions.Expression.New(typeof(Dictionary<int, string>));

Console.WriteLine(newDictionaryExpression.ToString());

// This code produces the following output: 
// 
// new Dictionary`2()

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

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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