XPATH Help

Question

User-990300661 posted

I'm trying to consume an RSS feed into a repeater to display the title and an image in a list item.  The feed can be seen at http://coastalscience.noaa.gov/news/feed/

Some descriptions have an image, and some do not.  What I would like to do is get all nodes (maybe the last 5) that have a description with an image.  Example:

<item>
  <title>Community Leaders Explore Coastal Ocean Science</title>
 <description>
 <![CDATA[
 <p><img src="###" class="###" alt="###" style="###" />
    Regular text appears here</p> 
<p>The post <a rel="nofollow" href="http://coastalscience.noaa.gov/news/topics/misc/community-leaders-explore-coastal-ocean-science-beaufort-laboratory/">Community Leaders Explore Coastal Ocean Science at Beaufort Laboratory</a> appeared first on <a rel="nofollow" href="http://coastalscience.noaa.gov/news">News and Feature Stories</a>.</p>
]]>
  </description>
</item>

So far, I've figured out how to list only the last 5 items from the following code, but I'm not sure where to go next:

<asp:XmlDataSource id="genericXmlDataSource" runat="server"
        datafile="http://coastalscience.noaa.gov/news/feed/" XPath="rss/channel/item[position()<6]" >
</asp:XmlDataSource>

Can anyone point me in the right direction please?

Answer 1

User697462465 posted

Hi Karls,

We can use the <%#XPath("path")%> to bind the xml result to server control, like Repeater,GridView etc.

So, please try to use the following code to display your result:

<asp:Repeater runat="server" DataSourceID="genericXmlDataSource">
            <ItemTemplate>
                Title:<asp:Label runat="server" Text='<%#XPath("title") %>'></asp:Label><br />
                Description:<%#XPath("description") %><br />
            </ItemTemplate>
        </asp:Repeater>
    <asp:XmlDataSource id="genericXmlDataSource" runat="server"
        datafile="http://coastalscience.noaa.gov/news/feed/" XPath="rss/channel/item[position()<6]" >
</asp:XmlDataSource>

More information about XmlDataSource please refer to:
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.xmldatasource(v=vs.110).aspx

Hope it helps.

Best Regards,
Terry Guo

Answer 2

User-990300661 posted

Hi Terry, 

I had that part, but failed to post it, sorry.

<asp:Repeater ID="rptSlider" runat="server" datasourceid="genericXmlDataSource" enableviewstate="false">
    <headerTemplate><ul></headerTemplate>
        <ItemTemplate>
            <li><asp:hyperlink runat="server" navigateurl='<%#XPath("link")%>'
                    text='<%#XPath("title")%>' />
        <img src="##" alt="###"/></li>
         </ItemTemplate>
     <footerTemplate></ul></footerTemplate>
</asp:Repeater>

What I'm trying to figure out is how to target and retrieve the items where a description has an image in it, and display the image itself in the repeater.

Thanks

Answer 3

User697462465 posted

Hi Karls,

The XPath can't find the elements from CDATA fragment, but we can use the Regex to solve it, like this:

<asp:Repeater runat="server" DataSourceID="genericXmlDataSource">
            <ItemTemplate>
                Title:<asp:Label runat="server" Text='<%#XPath("title") %>'></asp:Label><br />
                Description:<%# System.Text.RegularExpressions.Regex.Match(XPath("description").ToString(),"<img[^>]+src\\s*=\\s*['\"]([^'\"]+)['\"][^>]*>").Value %><br />
            </ItemTemplate>
        </asp:Repeater>

More information about Regex please refer to:
http://msdn.microsoft.com/en-us/library/ms228595.aspx

Hope it helps.

Best Regards,
Terry Guo

Answer 4

User-990300661 posted

Thanks Terry, this helped me figure it out.

Cheers!