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Type.MakePointerType Method

Definition

Returns a Type object that represents a pointer to the current type.

public:
 abstract Type ^ MakePointerType();
public:
 virtual Type ^ MakePointerType();
public abstract Type MakePointerType ();
public virtual Type MakePointerType ();
abstract member MakePointerType : unit -> Type
abstract member MakePointerType : unit -> Type
override this.MakePointerType : unit -> Type
Public MustOverride Function MakePointerType () As Type
Public Overridable Function MakePointerType () As Type

Returns

A Type object that represents a pointer to the current type.

Exceptions

The invoked method is not supported in the base class.

The current type is TypedReference.

-or-

The current type is a ByRef type. That is, IsByRef returns true.

Examples

The following code example creates array, ref (ByRef in Visual Basic), and pointer types for the Test class.

using namespace System;
using namespace System::Reflection;

public ref class Example
{
public:
   static void Main()
   {
      // Create a Type object that represents a one-dimensional
      // array of Example objects.
      Type^ t = Example::typeid->MakeArrayType();
      Console::WriteLine( L"\r\nArray of Example: {0}", t );
      
      // Create a Type object that represents a two-dimensional
      // array of Example objects.
      t = Example::typeid->MakeArrayType( 2 );
      Console::WriteLine( L"\r\nTwo-dimensional array of Example: {0}", t );
      
      // Demonstrate an exception when an invalid array rank is
      // specified.
      try
      {
         t = Example::typeid->MakeArrayType(  -1 );
      }
      catch ( Exception^ ex ) 
      {
         Console::WriteLine( L"\r\n{0}", ex );
      }
      
      // Create a Type object that represents a ByRef parameter
      // of type Example.
      t = Example::typeid->MakeByRefType();
      Console::WriteLine( L"\r\nByRef Example: {0}", t );
      
      // Get a Type object representing the Example class, a
      // MethodInfo representing the "Test" method, a ParameterInfo
      // representing the parameter of type Example, and finally
      // a Type object representing the type of this ByRef parameter.
      // Compare this Type object with the Type object created using
      // MakeByRefType.
      Type^ t2 = Example::typeid;
      MethodInfo^ mi = t2->GetMethod( L"Test" );
      ParameterInfo^ pi = mi->GetParameters()[ 0 ];
      Type^ pt = pi->ParameterType;
      Console::WriteLine( L"Are the ByRef types equal? {0}", (t == pt) );
      
      // Create a Type object that represents a pointer to an
      // Example object.
      t = Example::typeid->MakePointerType();
      Console::WriteLine( L"\r\nPointer to Example: {0}", t );
   }

   // A sample method with a ByRef parameter.
   //
   void Test( interior_ptr<Example^> /*e*/ )
   {
   }
};

int main()
{
   Example::Main();
}

/* This example produces output similar to the following:

Array of Example: Example[]

Two-dimensional array of Example: Example[,]

System.IndexOutOfRangeException: Index was outside the bounds of the array.
   at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
   at Example.Main()

ByRef Example: Example&
Are the ByRef types equal? True

Pointer to Example: Example*

 */
using System;
using System.Reflection;

public class Example
{
    public static void Main()
    {
        // Create a Type object that represents a one-dimensional
        // array of Example objects.
        Type t = typeof(Example).MakeArrayType();
        Console.WriteLine("\r\nArray of Example: {0}", t);

        // Create a Type object that represents a two-dimensional
        // array of Example objects.
        t = typeof(Example).MakeArrayType(2);
        Console.WriteLine("\r\nTwo-dimensional array of Example: {0}", t);

        // Demonstrate an exception when an invalid array rank is
        // specified.
        try
        {
            t = typeof(Example).MakeArrayType(-1);
        }
        catch(Exception ex)
        {
            Console.WriteLine("\r\n{0}", ex);
        }

        // Create a Type object that represents a ByRef parameter
        // of type Example.
        t = typeof(Example).MakeByRefType();
        Console.WriteLine("\r\nByRef Example: {0}", t);

        // Get a Type object representing the Example class, a
        // MethodInfo representing the "Test" method, a ParameterInfo
        // representing the parameter of type Example, and finally
        // a Type object representing the type of this ByRef parameter.
        // Compare this Type object with the Type object created using
        // MakeByRefType.
        Type t2 = typeof(Example);
        MethodInfo mi = t2.GetMethod("Test");
        ParameterInfo pi = mi.GetParameters()[0];
        Type pt = pi.ParameterType;
        Console.WriteLine("Are the ByRef types equal? {0}", (t == pt));

        // Create a Type object that represents a pointer to an
        // Example object.
        t = typeof(Example).MakePointerType();
        Console.WriteLine("\r\nPointer to Example: {0}", t);
    }

    // A sample method with a ByRef parameter.
    //
    public void Test(ref Example e)
    {
    }
}

/* This example produces output similar to the following:

Array of Example: Example[]

Two-dimensional array of Example: Example[,]

System.IndexOutOfRangeException: Index was outside the bounds of the array.
   at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
   at Example.Main()

ByRef Example: Example&
Are the ByRef types equal? True

Pointer to Example: Example*

 */
type Example() =
    // A sample method with a ByRef parameter.
    member _.Test(e: Example byref) = ()

do
    // Create a Type object that represents a one-dimensional
    // array of Example objects.
    let t = typeof<Example>.MakeArrayType()
    printfn $"\r\nArray of Example: {t}"

    // Create a Type object that represents a two-dimensional
    // array of Example objects.
    let t = typeof<Example>.MakeArrayType 2
    printfn $"\r\nTwo-dimensional array of Example: {t}"

    // Demonstrate an exception when an invalid array rank is
    // specified.
    try
        let t = typeof<Example>.MakeArrayType -1
        ()
    with ex ->
        printfn $"\r\n{ex}"

    // Create a Type object that represents a ByRef parameter
    // of type Example.
    let t = typeof<Example>.MakeByRefType()
    printfn $"\r\nByRef Example: {t}"

    // Get a Type object representing the Example class, a
    // MethodInfo representing the "Test" method, a ParameterInfo
    // representing the parameter of type Example, and finally
    // a Type object representing the type of this ByRef parameter.
    // Compare this Type object with the Type object created using
    // MakeByRefType.
    let t2 = typeof<Example>
    let mi = t2.GetMethod "Test"
    let pi = mi.GetParameters()[0]
    let pt = pi.ParameterType
    printfn $"Are the ByRef types equal? {t = pt}"

    // Create a Type object that represents a pointer to an
    // Example object.
    let t = typeof<Example>.MakePointerType()
    printfn $"\r\nPointer to Example: {t}"

(* This example produces output similar to the following:

Array of Example: Example[]

Two-dimensional array of Example: Example[,]

System.IndexOutOfRangeException: Index was outside the bounds of the array.
   at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
   at Example.Main()

ByRef Example: Example&
Are the ByRef types equal? True

Pointer to Example: Example*
 *)
Imports System.Reflection

Public Class Example
    Public Shared Sub Main()
        ' Create a Type object that represents a one-dimensional
        ' array of Example objects.
        Dim t As Type = GetType(Example).MakeArrayType()
        Console.WriteLine(vbCrLf & "Array of Example: " & t.ToString())

        ' Create a Type object that represents a two-dimensional
        ' array of Example objects.
        t = GetType(Example).MakeArrayType(2)
        Console.WriteLine(vbCrLf & "Two-dimensional array of Example: " & t.ToString())

        ' Demonstrate an exception when an invalid array rank is
        ' specified.
        Try
            t = GetType(Example).MakeArrayType(-1)
        Catch ex As Exception
            Console.WriteLine(vbCrLf & ex.ToString())
        End Try

        ' Create a Type object that represents a ByRef parameter
        ' of type Example.
        t = GetType(Example).MakeByRefType()
        Console.WriteLine(vbCrLf & "ByRef Example: " & t.ToString())

        ' Get a Type object representing the Example class, a
        ' MethodInfo representing the "Test" method, a ParameterInfo
        ' representing the parameter of type Example, and finally
        ' a Type object representing the type of this ByRef parameter.
        ' Compare this Type object with the Type object created using
        ' MakeByRefType.
        Dim t2 As Type = GetType(Example)
        Dim mi As MethodInfo = t2.GetMethod("Test")
        Dim pi As ParameterInfo = mi.GetParameters()(0)
        Dim pt As Type = pi.ParameterType
        Console.WriteLine("Are the ByRef types equal? " & (t Is pt))

        ' Create a Type object that represents a pointer to an
        ' Example object.
        t = GetType(Example).MakePointerType()
        Console.WriteLine(vbCrLf & "Pointer to Example: " & t.ToString())
    End Sub

    ' A sample method with a ByRef parameter.
    '
    Public Sub Test(ByRef e As Example)
    End Sub
End Class

' This example produces output similar to the following:
'
'Array of Example: Example[]
'
'Two-dimensional array of Example: Example[,]
'
'System.IndexOutOfRangeException: Index was outside the bounds of the array.
'   at System.RuntimeType.MakeArrayType(Int32 rank) in c:\vbl\ndp\clr\src\BCL\System\RtType.cs:line 2999
'   at Example.Main()
'
'ByRef Example: Example&
'Are the ByRef types equal? True
'
'Pointer to Example: Example*

Remarks

The MakePointerType method provides a way to generate pointer types for parameter lists.

Using the syntax of Microsoft intermediate language (MSIL), if the current Type object represents Int32, this method returns a Type object representing Int32*.

Applies to

See also