TemplateControl.XPath Method

Definition

Namespace:

System.Web.UI

Assembly:

System.Web.dll

Provides support for parsing and evaluating an XPath data-binding expression against an object at run time.

Overloads

XPath(String, String, IXmlNamespaceResolver)	Evaluates an XPath data-binding expression using the specified prefix and namespace mappings for namespace resolution and the specified format string to display the result.
XPath(String, IXmlNamespaceResolver)	Evaluates an XPath data-binding expression using the specified prefix and namespace mappings for namespace resolution.
XPath(String)	Evaluates an XPath data-binding expression.
XPath(String, String)	Evaluates an XPath data-binding expression using the specified format string to display the result.

XPath(String, String, IXmlNamespaceResolver)

Evaluates an XPath data-binding expression using the specified prefix and namespace mappings for namespace resolution and the specified format string to display the result.

protected public:
 System::String ^ XPath(System::String ^ xPathExpression, System::String ^ format, System::Xml::IXmlNamespaceResolver ^ resolver);

protected internal string XPath (string xPathExpression, string format, System.Xml.IXmlNamespaceResolver resolver);

member this.XPath : string * string * System.Xml.IXmlNamespaceResolver -> string

Protected Friend Function XPath (xPathExpression As String, format As String, resolver As IXmlNamespaceResolver) As String

Parameters

xPathExpression

String

The XPath expression to evaluate. For more information, see XPathBinder.

format

String

A .NET Framework format string to apply to the result.

resolver

IXmlNamespaceResolver

A set of prefix and namespace mappings used for namespace resolution.

Returns

String

A string that results from the evaluation of the data-binding expression and conversion to a string type.

Exceptions

InvalidOperationException

The data-binding method can be used only for controls contained on a Page.

Remarks

The XPath method calls the XPathBinder.Eval method using the GetDataItem method to resolve the IXPathNavigable object reference that the expression is evaluated against.

See also

• XPathBinder
• Formatting Types in .NET

XPath(String, IXmlNamespaceResolver)

Evaluates an XPath data-binding expression using the specified prefix and namespace mappings for namespace resolution.

protected public:
 System::Object ^ XPath(System::String ^ xPathExpression, System::Xml::IXmlNamespaceResolver ^ resolver);

protected internal object XPath (string xPathExpression, System.Xml.IXmlNamespaceResolver resolver);

member this.XPath : string * System.Xml.IXmlNamespaceResolver -> obj

Protected Friend Function XPath (xPathExpression As String, resolver As IXmlNamespaceResolver) As Object

Parameters

xPathExpression

String

The XPath expression to evaluate. For more information, see XPathBinder.

resolver

IXmlNamespaceResolver

A set of prefix and namespace mappings used for namespace resolution.

Returns

Object

An object that results from the evaluation of the data-binding expression.

Exceptions

InvalidOperationException

The data-binding method can be used only for controls contained on a Page.

Remarks

The XPath method calls the XPathBinder.Eval method using the GetDataItem method to resolve the IXPathNavigable object reference that the expression is evaluated against.

See also

• XPathBinder

XPath(String)

Evaluates an XPath data-binding expression.

protected public:
 System::Object ^ XPath(System::String ^ xPathExpression);

protected internal object XPath (string xPathExpression);

member this.XPath : string -> obj

Protected Friend Function XPath (xPathExpression As String) As Object

Parameters

xPathExpression

String

The XPath expression to evaluate. For more information, see XPathBinder.

Returns

Object

An object that results from the evaluation of the data-binding expression.

Exceptions

InvalidOperationException

The data-binding method can be used only for controls contained on a Page.

Examples

The following code example demonstrates how to use the XPath method in a Repeater control.

<%@ 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>TemplateControl XPath and XPathSelect Example</title>
</head>
<body>
    <h3>TemplateControl XPath Example</h3>
    <form id="form1" runat="server">
    <div>
      <asp:XmlDataSource
        id="XmlDataSource1" 
        runat="server"
        XPath="contacts" 
        DataFile="contacts.xml" />    
      <asp:FormView 
        id="FormView1" 
        runat="server" 
        DataSourceID="XmlDataSource1">
        <ItemTemplate>
          <hr />
          <asp:Repeater 
            id="Repeater1" 
            runat="server" 
            DataSource='<%# XPathSelect("contact") %>' >
            <ItemTemplate>
              Name: <%# XPath("name") %> <br />
              Note: <%# XPath("note") %> <br />
              <hr />
            </ItemTemplate>
          </asp:Repeater>
        </ItemTemplate>
      </asp:FormView>
    </div>
    </form>
</body>
</html>

<%@ Page Language="VB" %>

<!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 id="Head1" runat="server">
    <title>TemplateControl XPath Example</title>
</head>
<body>
    <h3>TemplateControl XPath and XPathSelect Example</h3>
    <form id="form1" runat="server">
    <div>
      <asp:XmlDataSource
        id="XmlDataSource1" 
        runat="server"
        XPath="contacts" 
        DataFile="contacts.xml" />    
      <asp:FormView 
        id="FormView1" 
        runat="server" 
        DataSourceID="XmlDataSource1">
        <ItemTemplate>
          <hr />
          <asp:Repeater 
            id="Repeater1" 
            runat="server" 
            DataSource='<%# XPathSelect("contact") %>' >
            <ItemTemplate>
              Name: <%# XPath("name") %> <br />
              Note: <%# XPath("note") %> <br />
              <hr />
            </ItemTemplate>
          </asp:Repeater>
        </ItemTemplate>
      </asp:FormView>
    </div>
    </form>
</body>
</html>

The following test XML data can be used in the preceding code example.

<contacts>  
   <contact id="1">  
     <name>contact name 1</name>  
     <note>contact note 1</note>  
   </contact>  
   <contact id="2">  
     <name>contact name 2</name>  
     <note>contact note 2</note>  
   </contact>  
</contacts>  

Remarks

The XPath method calls the XPathBinder.Eval method using the GetDataItem method to resolve the IXPathNavigable object reference that the expression is evaluated against.

See also

• XPathBinder

XPath(String, String)

Evaluates an XPath data-binding expression using the specified format string to display the result.

protected public:
 System::String ^ XPath(System::String ^ xPathExpression, System::String ^ format);

protected internal string XPath (string xPathExpression, string format);

member this.XPath : string * string -> string

Protected Friend Function XPath (xPathExpression As String, format As String) As String

Parameters

xPathExpression

String

The XPath expression to evaluate. For more information, see XPathBinder.

format

String

A .NET Framework format string to apply to the result.

Returns

String

A string that results from the evaluation of the data-binding expression and conversion to a string type.

Exceptions

InvalidOperationException

The data-binding method can be used only for controls contained on a Page.

Remarks

The XPath method calls the XPathBinder.Eval method using the GetDataItem method to resolve the IXPathNavigable object reference that the expression is evaluated against.

See also

• XPathBinder
• Formatting Types in .NET