GetUnderlyingType Method

Enum.GetUnderlyingType Method

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Returns the underlying type of the specified enumeration.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
Public Shared Function GetUnderlyingType ( _
	enumType As Type _
) As Type

Parameters

enumType
Type: System.Type
The enumeration whose underlying type will be retrieved.

Return Value

Type: System.Type
The underlying type of enumType.

ExceptionCondition
ArgumentNullException

enumType is Nothing.

ArgumentException

enumType is not an Enum.

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.

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


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

Show:
© 2017 Microsoft