Enum.GetUnderlyingType Method
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Returns the underlying type of the specified enumeration.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
<ComVisibleAttribute(True)> _
Public Shared Function GetUnderlyingType ( _
enumType As Type _
) As Type
[ComVisibleAttribute(true)]
public static Type GetUnderlyingType(
Type enumType
)
Parameters
- enumType
Type: System.Type
The enumeration whose underlying type will be retrieved.
Return Value
Type: System.Type
The underlying type of enumType.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentNullException | enumType is nulla null reference (Nothing in Visual Basic). |
| ArgumentException | enumType is not an Enum. |
Remarks
The Enum structure enables values to be represented as named constants. The data type of the enumeration's values is known as its underlying type. For example, the underlying type of the DayOfWeek enumeration, which consists of constants that represent each day of the week (DayOfWeek.Monday, DayOfWeek.Tuesday, and so on), is Int32.
Examples
The following example calls the GetUnderlyingType method to display the underlying type of some enumeration members.
Module Example
Public Sub Demo(outputBlock As System.Windows.Controls.TextBlock)
Dim enumValues() As [Enum] = { DayOfWeek.Monday, PlatformID.Win32NT,
DateTimeKind.Utc, StringComparison.Ordinal }
outputBlock.FontFamily = New FontFamily("Courier New")
outputBlock.Text += String.Format("{0,-10} {1, 18} {2,15}",
"Member", "Enumeration", "Underlying Type") + vbCrLf
outputBlock.Text += vbCrLf
For Each enumValue In enumValues
DisplayEnumInfo(outputBlock, enumValue)
Next
End Sub
Sub DisplayEnumInfo(outputBlock As System.Windows.Controls.TextBlock,
enumValue As [Enum])
Dim enumType As Type = enumValue.GetType()
Dim underlyingType As Type = [Enum].GetUnderlyingType(enumType)
outputBlock.Text += String.Format("{0,-10} {1, 18} {2,15}",
enumValue, enumType.Name,
underlyingType.Name) + vbCrLf
End Sub
End Module
' The example displays the following output:
' Member Enumeration Underlying Type
'
' Monday DayOfWeek Int32
' Win32NT PlatformID Int32
' Utc DateTimeKind Int32
' Ordinal StringComparison Int32
using System;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
Enum[] enumValues = { DayOfWeek.Monday, PlatformID.Win32NT,
DateTimeKind.Utc, StringComparison.Ordinal };
outputBlock.FontFamily = new System.Windows.Media.FontFamily("Courier New");
outputBlock.Text += String.Format("{0,-10} {1, 18} {2,15}\n\n",
"Member", "Enumeration", "Underlying Type");
foreach (var enumValue in enumValues)
DisplayEnumInfo(outputBlock, enumValue);
}
static void DisplayEnumInfo(System.Windows.Controls.TextBlock outputBlock,
Enum enumValue)
{
Type enumType = enumValue.GetType();
Type underlyingType = Enum.GetUnderlyingType(enumType);
outputBlock.Text += String.Format("{0,-10} {1, 18} {2,15}\n",
enumValue, enumType.Name,
underlyingType.Name);
}
}
// The example displays the following output:
// Member Enumeration Underlying Type
//
// Monday DayOfWeek Int32
// Win32NT PlatformID Int32
// Utc DateTimeKind Int32
// Ordinal StringComparison Int32
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.