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Type.HasElementType Property

Gets a value indicating 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
Public ReadOnly Property HasElementType As Boolean

Property Value

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

Implements

_Type.HasElementType

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

If the current Type represents a generic type, or a type parameter in the definition of a generic type or generic method, this property always returns false.

The following example returns true or false depending on whether or not the object is an array, a reference type, or a pointer.


Imports System
Imports System.Reflection
Imports System.Runtime.InteropServices

Public Class Example

    ' This method is for demonstration purposes.
    Public Shared Sub Test(ByRef x As Integer, <Out> ByRef y As Integer)
    End Sub

    Public Shared Sub Main()
        ' All of the following display 'True'.

        ' Define an array, get its type, and display HasElementType. 
        Dim nums() As Integer = {1, 1, 2, 3, 5, 8, 13}
        Dim t As Type = nums.GetType()
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' Test an array type without defining an array.
        t = GetType(Example())
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' When you use Reflection Emit to emit dynamic methods and
        ' assemblies, you can create array types using MakeArrayType.
        ' The following creates the type 'array of Example'.
        t = GetType(Example).MakeArrayType()
        Console.WriteLine("HasElementType is '{0}' for array types.", t.HasElementType)

        ' When you reflect over methods, HasElementType is true for
        ' ref, out, and pointer parameter types. The following 
        ' gets the Test method, defined above, and examines its
        ' parameters.
        Dim mi As MethodInfo = GetType(Example).GetMethod("Test")
        Dim parms() As ParameterInfo = mi.GetParameters()
        t = parms(0).ParameterType
        Console.WriteLine("HasElementType is '{0}' for ref parameter types.", t.HasElementType)
        t = parms(1).ParameterType
        Console.WriteLine("HasElementType is '{0}' for <Out> parameter types.", t.HasElementType)

        ' When you use Reflection Emit to emit dynamic methods and
        ' assemblies, you can create pointer and ByRef types to use
        ' when you define method parameters.
        t = GetType(Example).MakePointerType()
        Console.WriteLine("HasElementType is '{0}' for pointer types.", t.HasElementType)
        t = GetType(Example).MakeByRefType()
        Console.WriteLine("HasElementType is '{0}' for ByRef types.", t.HasElementType)
    End Sub 

End Class


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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

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