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MemberInitExpression Class

Represents calling a constructor and initializing one or more members of the new object.

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

'Declaration
Public NotInheritable Class MemberInitExpression _
	Inherits Expression
'Usage
Dim instance As MemberInitExpression

Use the MemberInit factory methods to create a MemberInitExpression.

The value of the NodeType property of a MemberInitExpression is MemberInit.

The following example creates a MemberInitExpression that represents the initialization of two members of a new object.

Class Animal
    Public Species As String 
    Public Age As Integer 
End Class 

Shared Sub CreateMemberInitExpression()
    Dim newAnimal As System.Linq.Expressions.NewExpression = _
        System.Linq.Expressions.Expression.[New](Type.GetType("ExpressionVB.MemberInitExample+Animal"))

    Dim speciesMember As System.Reflection.MemberInfo = _
        Type.GetType("ExpressionVB.MemberInitExample+Animal").GetMember("Species")(0)
    Dim ageMember As System.Reflection.MemberInfo = _
        Type.GetType("ExpressionVB.MemberInitExample+Animal").GetMember("Age")(0)

    ' Create a MemberBinding object for each member 
    ' that you want to initialize. 
    Dim speciesMemberBinding As System.Linq.Expressions.MemberBinding = _
        System.Linq.Expressions.Expression.Bind( _
            speciesMember, _
            System.Linq.Expressions.Expression.Constant("horse"))
    Dim ageMemberBinding As System.Linq.Expressions.MemberBinding = _
        System.Linq.Expressions.Expression.Bind( _
            ageMember, _
            System.Linq.Expressions.Expression.Constant(12))

    ' Create a MemberInitExpression that represents initializing 
    ' two members of the 'Animal' class. 
    Dim memberInitExpression As System.Linq.Expressions.MemberInitExpression = _
        System.Linq.Expressions.Expression.MemberInit( _
            newAnimal, _
            speciesMemberBinding, _
            ageMemberBinding)

    Console.WriteLine(memberInitExpression.ToString())

    ' This code produces the following output: 
    
    ' new Animal() {Species = "horse", Age = 12} 
End Sub

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.MemberInitExpression

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5
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