Explicit Conversion (XAttribute to Nullable(Guid))

XAttribute Narrowing Conversion (XAttribute to Nullable(Of Guid))

 
equivalentCodeEntityop_Explicit(XAttribute attribute)

Cast the value of this XAttribute to a Nullable(Of T) of Guid.

This API is not CLS-compliant.

Namespace:   System.Xml.Linq
Assembly:  System.Xml.Linq (in System.Xml.Linq.dll)

Public Shared Narrowing Operator CType (
	attribute As XAttribute
) As Nullable(Of Guid)

Parameters

attribute
Type: System.Xml.Linq.XAttribute

The XAttribute to cast to a Nullable(Of T) of Guid.

Return Value

Type: System.Nullable(Of Guid)

A Nullable(Of T) of Guid that contains the content of this XAttribute.

Exception Condition
FormatException

The attribute does not contain a valid Guid value.

The following example creates an attribute with guid content. It then retrieves the value by casting to Nullable(Of T) of Guid.


                Dim root As XElement = <Root Att=<%= New Guid("3c1cc55b-baff-4b7a-9d17-077af3aa5730") %>/>
Dim value As Nullable(Of Guid) = CType(root.Attribute("Att"), Nullable(Of Guid))
Console.WriteLine("Nullable Guid: value={0}", IIf(value.HasValue, value.ToString(), "null"))

This example produces the following output:

Nullable Guid: value=3c1cc55b-baff-4b7a-9d17-077af3aa5730

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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