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XElement Explicit Conversion (XElement to Boolean)

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

Cast the value of this XElement to a 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 Boolean

public static explicit operator bool (
    XElement element
)

Parameters

Return Value

Type: System.Boolean
A Boolean that contains the content of this XElement.

Exceptions

Exception Condition
FormatException

The element does not contain a valid Boolean value.
ArgumentNullException

The element parameter is nulla null reference (Nothing in Visual Basic).

Remarks

When converting to 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 some elements with boolean values. It then casts them to Boolean.

Dim output As New StringBuilder
Dim root As XElement = New XElement("Root", _
    New XElement("BoolValue1", True), _
    New XElement("BoolValue2", False))

Dim bool1 As Boolean = CBool(root.Element("BoolValue1"))
Dim bool2 As Boolean = CBool(root.Element("BoolValue2"))
output.Append(String.Format("(bool)BoolValue1={0}", bool1))
output.Append(Environment.NewLine)
output.Append(String.Format("(bool)BoolValue2={0}", bool2))
output.Append(Environment.NewLine)

OutputTextBlock.Text = output.ToString()

StringBuilder output = new StringBuilder();
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");
output.Append("(bool)BoolValue1=" + bool1 + Environment.NewLine);
output.Append("(bool)BoolValue2=" + bool2 + Environment.NewLine);

OutputTextBlock.Text = output.ToString();

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.