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MemberExpression Class

Definition

Represents accessing a field or property.

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

Examples

The following example creates a MemberExpression that represents getting the value of a field member.

class Animal
{
    public string species;
}

public static void CreateFieldExpression()
{
    Animal horse = new Animal();

    // Create a MemberExpression that represents getting
    // the value of the 'species' field of class 'Animal'.
    System.Linq.Expressions.MemberExpression memberExpression =
        System.Linq.Expressions.Expression.Field(
            System.Linq.Expressions.Expression.Constant(horse),
            "species");

    Console.WriteLine(memberExpression.ToString());

    // This code produces the following output:
    //
    // value(CodeSnippets.FieldExample+Animal).species
}
Class Animal
    Dim species As String
End Class

Shared Sub CreateFieldExpression()
    Dim horse As New Animal

    ' Create a MemberExpression that represents getting
    ' the value of the 'species' field of class 'Animal'.
    Dim memberExpression As System.Linq.Expressions.MemberExpression = _
        System.Linq.Expressions.Expression.Field( _
            System.Linq.Expressions.Expression.Constant(horse), _
            "species")

    Console.WriteLine(memberExpression.ToString())

    ' This code produces the following output:
    '
    ' value(ExpressionVB.FieldExample+Animal).species
End Sub

Remarks

Use the Field, Property or PropertyOrField factory methods to create a MemberExpression.

The value of the NodeType property of a MemberExpression is MemberAccess.

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)
Expression

Gets the containing object of the field or property.

Member

Gets the field or property to be accessed.

NodeType

Returns the node type of this Expression.

NodeType

Gets the node type of this Expression.

(Inherited from Expression)
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(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