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XElement Explicit Conversion (XElement to Nullable<Guid>)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Cast the value of this XElement to a Nullable<T> of Guid.

This API is not CLS-compliant. 

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

Syntax

'Declaration
Public Shared Narrowing Operator CType ( _
    element As XElement _
) As Nullable(Of Guid)

public static explicit operator Nullable<Guid> (
    XElement element
)

Parameters

Return Value

Type: System.Nullable<Guid>
A Nullable<T> of Guid that contains the content of this XElement.

Exceptions

Exception Condition
FormatException

The element does not contain a valid Guid value.

Examples

The following example creates an element with guid content. It then retrieves the value by casting to Nullable<T> of Guid.

XElement root = new XElement("Root",
    new XElement("Value", new Guid("3c1cc55b-baff-4b7a-9d17-077af3aa5730"))
);
Guid? value = (Guid?)root.Element("Value");

Dim root As XElement = _ 
    <Root>
        <Value><%= New Guid("3c1cc55b-baff-4b7a-9d17-077af3aa5730") %></Value>
    </Root>
Dim value As Nullable(Of Guid) = CType(root.Element("Value"), Nullable(Of Guid))

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.