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XElement Explicit Conversion (XElement to Nullable<UInt64>)

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

Cast the value of this XElement to a Nullable<T> of UInt64.

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 ULong)

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

Parameters

Return Value

Type: System.Nullable<UInt64>
A Nullable<T> of UInt64 that contains the content of this XElement.

Exceptions

Exception Condition
FormatException

The element does not contain a valid UInt64 value.

Examples

The following example creates an element with unsigned long integer content. It then retrieves the value by casting to Nullable<T> of UInt64.

XElement root = new XElement("Root", 
    new XElement("Value", 9223372036854775807)
);
ulong? value = (ulong?)root.Element("Value");

Dim root As XElement = _ 
        <Root>
            <Value>9223372036854775807</Value>
        </Root>

Dim value As Nullable(Of ULong) = CType(root.Element("Value"), Nullable(Of ULong))

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.