次の方法で共有


XElement Explicit Conversion (XElement to Nullable<TimeSpan>)

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

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

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

Parameters

Return Value

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

Exceptions

Exception Condition
FormatException

The element does not contain a valid TimeSpan value.

Remarks

The value space of an attribute or element that contains time span content is closely related to duration content as described in ISO 8601. When creating an attribute or element that contains time span content, the attribute or element values are formatted per the W3C specification. For more information, see the NOTE-datetime W3C specification.

Behavior is lax when casting to a Nullable<T> of TimeSpan from an attribute or element. Even if the attribute or element value is not formatted exactly per the W3C specification, the value is appropriately converted to a Nullable<T> of TimeSpan.

Examples

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

XElement root = new XElement("Root",
    new XElement("Value", new TimeSpan(1, 5, 30))
);
TimeSpan? value = (TimeSpan?)root.Element("Value");
Dim root As XElement = _
    <Root>
        <Value><%= New TimeSpan(1, 5, 30) %></Value>
    </Root>
Dim value As Nullable(Of TimeSpan) = CType(root.Element("Value"), Nullable(Of TimeSpan))

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.