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Type.HasElementTypeImpl Method

When overridden in a derived class, implements the HasElementType property and determines whether the current Type encompasses or refers to another type; that is, whether the current Type is an array, a pointer, or is passed by reference.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
Protected MustOverride Function HasElementTypeImpl As Boolean

Return Value

Type: System.Boolean
true if the Type is an array, a pointer, or is passed by reference; otherwise, false.

For example, Type.GetType("Int32[]").HasElementTypeImpl returns true, but Type.GetType("Int32").HasElementTypeImpl returns false. HasElementTypeImpl also returns true for "Int32*" and "Int32&".

The following example defines the class MyTypeDelegator, which overrides the HasElementTypeImpl method. The main class checks for the HasElementType property and displays the element type.

Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic
Public Class MyTypeDelegator
    Inherits TypeDelegator
    Public myElementType As String = Nothing 
    Private myType As Type = Nothing 
    Public Sub New(ByVal myType As Type)
        MyBase.New(myType)
        Me.myType = myType
    End Sub 'New 
    ' Override Type.HasElementTypeImpl(). 
    Protected Overrides Function HasElementTypeImpl() As Boolean 
        ' Determine whether the type is an array. 
        If myType.IsArray Then
            myElementType = "array" 
            Return True 
        End If 
        ' Determine whether the type is a reference. 
        If myType.IsByRef Then
            myElementType = "reference" 
            Return True 
        End If 
        ' Determine whether the type is a pointer. 
        If myType.IsPointer Then
            myElementType = "pointer" 
            Return True 
        End If 
        ' The type is not a reference, array, or pointer type. 
        Return False 
    End Function 'HasElementTypeImpl
End Class 'MyTypeDelegator
Public Class Type_HasElementTypeImpl
    Public Shared Sub Main()
        Try 
            Dim myInt As Integer = 0
            Dim myArray(4) As Integer 
            Dim myType As New MyTypeDelegator(myArray.GetType())
            Console.WriteLine(ControlChars.NewLine + "Determine whether a variable refers to an array or pointer or reference type." + ControlChars.NewLine)
            ' Determine whether myType is an array, pointer, reference type.   
            If myType.HasElementType Then
                Console.WriteLine("The type of myArray is {0}.", myType.myElementType.ToString())
            Else
                Console.WriteLine("myArray is not an array, pointer, or reference type.")
            End If
            myType = New MyTypeDelegator(myInt.GetType())
            ' Determine whether myType is an array, pointer, reference type.  
            If myType.HasElementType Then
                Console.WriteLine("The type of myInt is {0}.", myType.myElementType.ToString())
            Else
                Console.WriteLine("myInt is not an array, pointer, or reference type.")
            End If 
        Catch e As Exception
            Console.WriteLine("Exception: {0}", e.Message.ToString())
        End Try 
    End Sub 'Main
End Class 'Type_HasElementTypeImpl

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

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
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