Updated: June 2010
Returns a Type object representing a one-dimensional array of the current type, with a lower bound of zero.
Assembly: mscorlib (in mscorlib.dll)
Public Overridable Function MakeArrayType As Typepublic virtual Type MakeArrayType()public:
virtual Type^ MakeArrayType()abstract MakeArrayType : unit -> Type
override MakeArrayType : unit -> Type Return Value
Type: SystemA Type object representing a one-dimensional array of the current type, with a lower bound of zero.
| Exception | Condition |
|---|---|
| NotSupportedException | The invoked method is not supported in the base class. Derived classes must provide an implementation. |
| TypeLoadException | The current type is TypedReference. -or- The current type is a ByRef type. That is, Type |
The MakeArrayType method provides a way to generate array types whose element types are computed at run time.
Note The common language runtime makes a distinction between vectors (that is, one-dimensional arrays that are always zero-based) and multidimensional arrays. A vector, which always has only one dimension, is not the same as a multidimensional array that happens to have only one dimension. This method overload can only be used to create vector types, and it is the only way to create a vector type. Use the MakeArrayType(Int32) method overload to create multidimensional array types.
The following code example creates array, ref (ByRef in Visual Basic), and pointer types for the Test class.
Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic
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*
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*
*/
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*
*/
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.Date | History | Reason |
|---|---|---|
June 2010 | Added missing TypeLoadException exception. | Customer feedback. |