NewExpression Class

Definition

Namespace:

System.Linq.Expressions

Assembly:

System.Linq.Expressions.dll

Source:

NewExpression.cs

Represents a constructor call.

public ref class NewExpression : System::Linq::Expressions::Expression, System::Linq::Expressions::IArgumentProvider

public class NewExpression : System.Linq.Expressions.Expression, System.Linq.Expressions.IArgumentProvider

type NewExpression = class
    inherit Expression
    interface IArgumentProvider

Public Class NewExpression
Inherits Expression
Implements IArgumentProvider

Inheritance

Object

Expression

NewExpression

Implements

IArgumentProvider

Examples

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()

' Create a NewExpression that represents constructing
' a new instance of Dictionary(Of Integer, String).
Dim newDictionaryExpression As System.Linq.Expressions.NewExpression = _
    System.Linq.Expressions.Expression.[New]( _
        Type.GetType("System.Collections.Generic.Dictionary`2[System.Int32, System.String]"))

Console.WriteLine(newDictionaryExpression.ToString())

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

Remarks

Use the New factory methods to create a NewExpression.

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

Properties

Arguments	Gets the arguments to the constructor.
CanReduce	Indicates 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)
Constructor	Gets the called constructor.
Members	Gets the members that can retrieve the values of the fields that were initialized with constructor arguments.
NodeType	Returns the node type of this Expression.
Type	Gets the static type of the expression that this Expression represents.

Methods

Accept(ExpressionVisitor)	Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall(MethodCallExpression).
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (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 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)
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(IEnumerable<Expression>)	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(ExpressionVisitor)	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)

Explicit Interface Implementations

IArgumentProvider.ArgumentCount	Gets the number of arguments to the expression tree node.
IArgumentProvider.GetArgument(Int32)	Returns the argument at index, throwing if index is out of bounds.