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NewArrayExpression Class

Definition

Represents creating a new array and possibly initializing the elements of the new array.

public ref class NewArrayExpression : System::Linq::Expressions::Expression
public ref class NewArrayExpression sealed : System::Linq::Expressions::Expression
public class NewArrayExpression : System.Linq.Expressions.Expression
public sealed class NewArrayExpression : System.Linq.Expressions.Expression
type NewArrayExpression = class
    inherit Expression
Public Class NewArrayExpression
Inherits Expression
Public NotInheritable Class NewArrayExpression
Inherits Expression
Inheritance
NewArrayExpression

Examples

The following example creates a NewArrayExpression object that represents creating and initializing a one-dimensional array of strings.

List<System.Linq.Expressions.Expression> trees =
    new List<System.Linq.Expressions.Expression>()
        { System.Linq.Expressions.Expression.Constant("oak"),
          System.Linq.Expressions.Expression.Constant("fir"),
          System.Linq.Expressions.Expression.Constant("spruce"),
          System.Linq.Expressions.Expression.Constant("alder") };

// Create an expression tree that represents creating and
// initializing a one-dimensional array of type string.
System.Linq.Expressions.NewArrayExpression newArrayExpression =
    System.Linq.Expressions.Expression.NewArrayInit(typeof(string), trees);

// Output the string representation of the Expression.
Console.WriteLine(newArrayExpression.ToString());

// This code produces the following output:
//
// new [] {"oak", "fir", "spruce", "alder"}
Dim trees As New System.Collections.Generic.List(Of System.Linq.Expressions.Expression) _
        (New System.Linq.Expressions.Expression() _
         {System.Linq.Expressions.Expression.Constant("oak"), _
          System.Linq.Expressions.Expression.Constant("fir"), _
          System.Linq.Expressions.Expression.Constant("spruce"), _
          System.Linq.Expressions.Expression.Constant("alder")})

' Create an expression tree that represents creating and  
' initializing a one-dimensional array of type string.
Dim newArrayExpression As System.Linq.Expressions.NewArrayExpression = _
    System.Linq.Expressions.Expression.NewArrayInit(Type.GetType("System.String"), trees)

' Output the string representation of the Expression.
Console.WriteLine(newArrayExpression.ToString())

' This code produces the following output:
'
' new [] {"oak", "fir", "spruce", "alder"}

The next example creates a NewArrayExpression object that represents creating a two-dimensional array of strings.

// Create an expression tree that represents creating a
// two-dimensional array of type string with bounds [3,2].
System.Linq.Expressions.NewArrayExpression newArrayExpression =
    System.Linq.Expressions.Expression.NewArrayBounds(
            typeof(string),
            System.Linq.Expressions.Expression.Constant(3),
            System.Linq.Expressions.Expression.Constant(2));

// Output the string representation of the Expression.
Console.WriteLine(newArrayExpression.ToString());

// This code produces the following output:
//
// new System.String[,](3, 2)
' Create an expression tree that represents creating a string
' array with rank 2 and bounds (3,2).
Dim newArrayExpression As System.Linq.Expressions.NewArrayExpression = _
    System.Linq.Expressions.Expression.NewArrayBounds( _
            Type.GetType("System.String"), _
            System.Linq.Expressions.Expression.Constant(3), _
            System.Linq.Expressions.Expression.Constant(2))

' Output the string representation of the Expression.
Console.WriteLine(newArrayExpression.ToString())

' This code produces the following output:
'
' new System.String[,](3, 2)

Remarks

The following table shows the different factory methods that you can use to create a NewArrayExpression depending on the NodeType you require.

NodeType Factory Methods
NewArrayBounds NewArrayBounds
NewArrayInit NewArrayInit

Properties

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)
Expressions

Gets the bounds of the array if the value of the NodeType property is NewArrayBounds, or the values to initialize the elements of the new array if the value of the NodeType property is NewArrayInit.

NodeType

Gets the node type of this Expression.

(Inherited from Expression)
Type

Gets the static type of the expression that this Expression represents.

Type

Gets the static type of the expression that this Expression represents.

(Inherited from Expression)

Methods

Accept(ExpressionVisitor)

Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall(MethodCallExpression).

Accept(ExpressionVisitor)

Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall(MethodCallExpression).

(Inherited from Expression)
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)

Applies to