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XElement Explicit Conversion (XElement to Nullable<Boolean>)

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

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

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 Boolean)

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

Parameters

Return Value

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

Exceptions

Exception Condition
FormatException

The element does not contain a valid Boolean value.

Remarks

When converting to Nullable<T> of Boolean from an attribute or element, allowed values are "0", "1", and any string that produces "true" or "false" after trimming and conversion to lower case.

Examples

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

XElement root = new XElement("Root", 
    new XElement("BoolValue1", true),
    new XElement("BoolValue2", false));
bool? bool1 = (bool?)root.Element("BoolValue1");
bool? bool2 = (bool?)root.Element("BoolValue2");

Dim root As XElement = _ 
        <Root>
            <BoolValue1>true</BoolValue1>
            <BoolValue2>false</BoolValue2>
        </Root>


Dim value1 As Nullable(Of Boolean) = CType(root.Element("BoolValue1"), Nullable(Of Boolean))
Dim value2 As Nullable(Of Boolean) = CType(root.Element("BoolValue2"), Nullable(Of Boolean))

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.