XmlDataSource.XPath Property
Assembly: System.Web (in System.Web.dll)
Property Value
Type: System.StringA string that represents an XPath expression that can be used to filter the data contained by the Data property or by the XML file indicated by the DataFile property. The default value is String.Empty.
| Exception | Condition |
|---|---|
| InvalidOperationException |
The document is loading. |
For more information on XPath data-binding expressions, see Binding a Tabular Control to the XmlDataSource Control.
The following code example demonstrates how to use an XmlDataSource control with a templated Repeater control to display XML data that has been filtered using an XPath expression. In this example, XPath syntax is used to filter the XML data when the XPath property of the data source control is set, and also binds elements of the Repeater control template to the XML data.
<%@ Page Language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>ASP.NET Example</title> </head> <body> <form id="form1" runat="server"> <asp:XmlDataSource id="XmlSource" DataFile="bookstore.xml" runat="server" XPath="bookstore/genre[@name='fiction']"/> <asp:Repeater DataSourceID="XmlSource" runat="server"> <ItemTemplate> <h1><%# XPath ("book/title") %></h1> <b>Price:</b> <%# XPath ("book/price") %> </ItemTemplate> </asp:Repeater> </form> </body> </html>
The XML file in the code example has the following data:
<bookstore>
<genre name="fiction">
<book ISBN="0000000000">
<title>Secrets of Silicon Valley</title>
<price>12.95</price>
<chapters>
<chapter num="1" name="Introduction" />
<chapter num="2" name="Body" />
<chapter num="3" name="Conclusion" />
</chapters>
</book>
</genre>
<genre name="novel">
<book genre="novel" ISBN="1111111111">
<title>Straight Talk About Computers</title>
<price>24.95</price>
<chapters>
<chapter num="1" name="Introduction" />
<chapter num="2" name="Body" />
<chapter num="3" name="Conclusion" />
</chapters>
</book>
</genre>
</bookstore>
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.