Type.MakeArrayType Method (Int32)
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Updated: June 2010
Returns a Type object representing an array of the current type, with the specified number of dimensions.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Overridable Function MakeArrayType ( _
rank As Integer _
) As Type
public virtual Type MakeArrayType(
int rank
)
Parameters
- rank
Type: System.Int32
The number of dimensions for the array. This number must be less than or equal to 32.
Return Value
Type: System.Type
A Type object representing an array of the current type, with the specified number of dimensions.
Exceptions
| Exception | Condition |
|---|---|
| IndexOutOfRangeException | rank is invalid. For example, 0 or negative. |
| NotSupportedException | The invoked method is not supported in the base class. |
| TypeLoadException | The current type is TypedReference. -or- The current type is a ByRef type. That is, Type.IsByRef returns true. -or- rank is greater than 32. |
Remarks
The MakeArrayType method provides a way to generate array types whose element types are computed at run time.
.gif "Note") 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. You cannot use this method overload to create a vector type; if rank is 1, this method overload returns a multidimensional array type that happens to have one dimension. Use the MakeArrayType() method overload to create vector types. |
Examples
The following code example creates array, ref (ByRef in Visual Basic), and pointer types for the Test class.
| Note: |
|---|
To run this example, see Building Examples That Use a Demo Method and a TextBlock Control. |
Imports System.Reflection
Public Class Example
Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
' Create a Type object that represents a one-dimensional
' array of Example objects.
Dim t As Type = GetType(Example).MakeArrayType()
outputBlock.Text &= vbCrLf & "Array of Example: " & t.ToString() & vbCrLf
' Create a Type object that represents a two-dimensional
' array of Example objects.
t = GetType(Example).MakeArrayType(2)
outputBlock.Text &= vbCrLf & "Two-dimensional array of Example: " & t.ToString() & vbCrLf
' Demonstrate an exception when an invalid array rank is
' specified.
Try
t = GetType(Example).MakeArrayType(-1)
Catch ex As Exception
outputBlock.Text &= vbCrLf & ex.ToString() & vbCrLf
End Try
' Create a Type object that represents a ByRef parameter
' of type Example.
t = GetType(Example).MakeByRefType()
outputBlock.Text &= vbCrLf & "ByRef Example: " & t.ToString() & vbCrLf
' 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
outputBlock.Text &= "Are the ByRef types equal? " & (t Is pt) & vbCrLf
' Create a Type object that represents a pointer to an
' Example object.
t = GetType(Example).MakePointerType()
outputBlock.Text &= vbCrLf & "Pointer to Example: " & t.ToString() & vbCrLf
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: SilverlightApplication.Example[]
'
'Two-dimensional array of Example: SilverlightApplication.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 SilverlightApplication.Example.Demo(TextBlock outputBlock)
'
'ByRef Example: SilverlightApplication.Example&
'Are the ByRef types equal? True
'
'Pointer to Example: SilverlightApplication.Example*
using System;
using System.Reflection;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
// Create a Type object that represents a one-dimensional
// array of Example objects.
Type t = typeof(Example).MakeArrayType();
outputBlock.Text += String.Format("\r\nArray of Example: {0}\n", t);
// Create a Type object that represents a two-dimensional
// array of Example objects.
t = typeof(Example).MakeArrayType(2);
outputBlock.Text += String.Format("\r\nTwo-dimensional array of Example: {0}\n", t);
// Demonstrate an exception when an invalid array rank is
// specified.
try
{
t = typeof(Example).MakeArrayType(-1);
}
catch (Exception ex)
{
outputBlock.Text += String.Format("\r\n{0}\n", ex);
}
// Create a Type object that represents a ByRef parameter
// of type Example.
t = typeof(Example).MakeByRefType();
outputBlock.Text += String.Format("\r\nByRef Example: {0}\n", 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;
outputBlock.Text += String.Format("Are the ByRef types equal? {0}\n", (t == pt));
// Create a Type object that represents a pointer to an
// Example object.
t = typeof(Example).MakePointerType();
outputBlock.Text += String.Format("\r\nPointer to Example: {0}\n", 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.Demo(TextBlock outputBlock)
ByRef Example: Example&
Are the ByRef types equal? True
Pointer to Example: Example*
*/
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.
Change History
Date |
History |
Reason |
|---|---|---|
June 2010 |
Added missing TypeLoadException exception. |
Customer feedback. |