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XElement Explicit Conversion (XElement to Nullable<Single>)

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

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

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 Single)

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

Parameters

Return Value

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

Exceptions

Exception Condition
FormatException

The element does not contain a valid Single value.

Examples

The following example creates an element with single precision floating point content. It then retrieves the value by casting to Nullable<T> of Single.

Dim output As New StringBuilder
Dim root As XElement = _
        <Root>
            <Value>3.402823e38</Value>
        </Root>
Dim value As Nullable(Of Single) = CType(root.Element("Value"), Nullable(Of Single))
output.Append(String.Format("Nullable Single: value={0}", IIf(value.HasValue, _
    value.ToString(), "null")))
output.Append(Environment.NewLine)
OutputTextBlock.Text = output.ToString()

StringBuilder output = new StringBuilder();
XElement root = new XElement("Root",
    new XElement("Value", 3.402823e38)
);
float? value = (float?)root.Element("Value");
output.Append("Nullable Single: value=" + value == null ? "null" : value.ToString());
output.Append(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.