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xmldatasource and xpath expression evaluation

Posted By:      Posted Date: September 02, 2010    Points: 0   Category :ASP.Net
 
Hi, I am working with XMLdatasource and trying to consume a XML file. Now problem is there are scenarios when a link is not available in the xml file. Like in the e.g. below: <a href='<%# XPath("link") %>' >  </a>  say "link" can or cannot be there in the file. Now when "link" is missing, this expression throws exception. How can I handle this exception so that it continues loading page normally or can I check "link" existence somehow? Thanks.


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I want to get the value of an xpath expression in rowdatabound event. But I get:
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Protected Sub gvSearchResults_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles gvSearchResults.RowDataBound
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help with xpath expression needed

  

I get an "Object reference not set to an instance of an object." with the following:

XML document
<response>

<lst name="facet_counts">
<lst name="facet_queries"/>

<lst name="facet_fields">

<lst name="hasphoto">
<int name="true">4</int>
<int name="false">2</int>
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</lst>
<lst name="facet_dates"/>
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XPath expression:
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OR
objXML.SelectSingleNode("response/lst[@name=""facet_counts""]/lst[@name=""facet_fields""]/lst[@name=""hasphoto""]/int[@name=""true""]").Innertext

But when I test it here: http://www.xmlme.com/XpathTool.aspx

The correct value (4) is returned...:s


MSXML2 or XmlDocument ? using an union Expression in XPath 2

  


Hallo, I'm using XPath for a long time by MSXML, now I tested some xml access with XmlDocument and have a problem with using XPath2.
 

This one works:

DOMDocument doc2 = new MSXML2.DOMDocument();
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This one works not:

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xmlDoc.LoadXml(xmlText);
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Best regards

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MSXML2 or XmlDocument ? using an union Expression in XPath 2

  


Hallo, I'm using XPath for a long time by MSXML, now I tested some xml access with XmlDocument and have a problem with using XPath2.
 

This one works:

DOMDocument doc2 = new MSXML2.DOMDocument();
MSXML2.doc2.loadXML(xmlText);
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This one works not:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xmlText);
XmlNode node = xmlDoc.SelectSingleNode("bla1/bla2/(ytype|xtype)");


Is there any explanation? Which class should I use in .NET for XPath 2 XML access ?

Best regards

Roy


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I have a XMLDataSource somewhat like:
<bookstore>
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Hi i am using xpath to loop through each node,

the xml is below i can get the value of "link" but i cant get the thumbnail value, have you got any ideas how i can do this, my code is below.

Thanks

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</item>

<item>

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</item>



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        {           
            //run the XPath query
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            //use the

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How to write lamda expression with ByRef/ref parameter in c# ??

The code below causing syntax error:

item.OnAction = (p1, p2, ref p3) => {
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   .....
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};


item.OnAction = (p1, p2, & p3) => {
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