How to read external XML with namespaces from .NET

[rupinderbatra]

Hi

I am trying to integrate Yahoo! shipping in one of my projects and facing the following error:

1. I am using the GET method to find data from Yahoo in XML format. A typical response is as given below:

<?xml version="1.0" encoding="ISO-8859-1"?>
<ResultSet xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:yahoo:prods" xsi:schemaLocation="urn:yahoo:prods http://api.shopping.yahoo.com/shoppingservice/v1/productsearch.xsd" totalResultsAvailable="5263" firstResultPosition="1" totalResultsReturned="10">
<Result>
<Catalog ID="3004510600">
<Url><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600]]></Url>
<ProductName><![CDATA[Harry Potter Collection:]]></ProductName>
<PriceFrom>100.13</PriceFrom>
<PriceTo>127.15</PriceTo>
<Thumbnail>
<Url><![CDATA[http://f3c.yahoofs.com/shopping/3061944/simg_t_t0439827604gif85?rm_____DFuy3NLrf]]></Url>
<Height>81</Height>
<Width>85</Width>
</Thumbnail>
<UserRating>
<MaxRating>5</MaxRating>
<NumRatings>4</NumRatings>
<AverageRating>4.5</AverageRating>
<RatingUrl><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600:page=u ser-reviews]]></RatingUrl>
<CreateRatingUrl><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600:page=p ost-reviews]]></CreateRatingUrl>
</UserRating>
</Catalog>
</Result>
</ResultSet>


2. I am trying to read the above using XMLDocument object. Using that, I am able to get a handle to the root object and also able to navigate through the child nodes sequentially.
3. However, I am not able to execute XPath queries on the XML due to the XML having namespace definitons.
4. I tried using NameSpaceManager but due to my lack of experience with XML namespaces, I am not able to continue further.

Can someone please help me out in this?

Thanks,
Rupinder

[misogsk]

Hi

I am trying to integrate Yahoo! shipping in one of my projects and facing the following error:

1. I am using the GET method to find data from Yahoo in XML format. A typical response is as given below:

<?xml version="1.0" encoding="ISO-8859-1"?>
<ResultSet xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:yahoo:prods" xsi:schemaLocation="urn:yahoo:prods http://api.shopping.yahoo.com/shoppingservice/v1/productsearch.xsd" totalResultsAvailable="5263" firstResultPosition="1" totalResultsReturned="10">
<Result>
<Catalog ID="3004510600">
<Url><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600]]></Url>
<ProductName><![CDATA[Harry Potter Collection:]]></ProductName>
<PriceFrom>100.13</PriceFrom>
<PriceTo>127.15</PriceTo>
<Thumbnail>
<Url><![CDATA[http://f3c.yahoofs.com/shopping/3061944/simg_t_t0439827604gif85?rm_____DFuy3NLrf]]></Url>
<Height>81</Height>
<Width>85</Width>
</Thumbnail>
<UserRating>
<MaxRating>5</MaxRating>
<NumRatings>4</NumRatings>
<AverageRating>4.5</AverageRating>
<RatingUrl><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600:page=u ser-reviews]]></RatingUrl>
<CreateRatingUrl><![CDATA[http://shopping.yahoo.com/p:Harry%20Potter%20Collection%3A:3004510600:page=p ost-reviews]]></CreateRatingUrl>
</UserRating>
</Catalog>
</Result>
</ResultSet>


2. I am trying to read the above using XMLDocument object. Using that, I am able to get a handle to the root object and also able to navigate through the child nodes sequentially.
3. However, I am not able to execute XPath queries on the XML due to the XML having namespace definitons.
4. I tried using NameSpaceManager but due to my lack of experience with XML namespaces, I am not able to continue further.

Can someone please help me out in this?

Thanks,
Rupinder

Hi,

You can use:
using System.Xml;
You will need XmlDocument class to load XML document.
To read xml file use XmlReader class, for more information go to http://msdn2.microsoft.com/en-us/library/system.xml.xmlreader_members.aspx

I hope this will help you.

[blackjack2150]

You have to create a NamspaceManager, providing the constructor the NameTable of the XmlDocument.

Add the required namespaces to the namespace manager, taking care that you write the correct prefix.

Then, in all the methods which use XPath, like for example SelectSingleNode, precede the xml node name with the prefix and a double-colon.

In your case, I think it would be smth like this:

XmlDocument doc = new XmlDocument();
doc.Load("myfile.xml");

XmlNamespaceManager man = new XmlNamespaceManager(doc.NameTable);

man.AddNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:yahoo:prods");

After this in all your XPath expressions, instead of ResultSet, use xsi:ResultSet.

GL.

[blackjack2150]

You have to create a NamspaceManager, providing the constructor the NameTable of the XmlDocument.

Add the required namespaces to the namespace manager, taking care that you write the correct prefix.

Then, in all the methods which use XPath, like for example SelectSingleNode, precede the xml node name with the prefix and a double-colon.

In your case, I think it would be smth like this:

XmlDocument doc = new XmlDocument();
doc.Load("myfile.xml");

XmlNamespaceManager man = new XmlNamespaceManager(doc.NameTable);

man.AddNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:yahoo:prods");

After this in all your XPath expressions, instead of ResultSet, use xsi:ResultSet.

GL.

I forgot to escape the quotes in the namespace string.

[rupinderbatra]

I forgot to escape the quotes in the namespace string.

XmlDocument doc = new XmlDocument();
doc.Load("myfile.xml");

XmlNamespaceManager man = new XmlNamespaceManager(doc.NameTable);

man.AddNamespace("xsi", "urn:yahoo:prods");

XMLNodeList NL_Results = doc.documentElement("//xsi:Result");

The above is working fine. However while trying to access second level nodes, I am not sure how to proceed.

I tried "//xsi:Catalog/xsi:Url" and "//xsi:Catalog/Url" but none of them helps.

Any help would be greatly appreciated.

Thanks,
Rupinder

[blackjack2150]

XmlDocument doc = new XmlDocument();
doc.Load("myfile.xml");

XmlNamespaceManager man = new XmlNamespaceManager(doc.NameTable);

man.AddNamespace("xsi", "urn:yahoo:prods");

XMLNodeList NL_Results = doc.documentElement("//xsi:Result");

The above is working fine. However while trying to access second level nodes, I am not sure how to proceed.

I tried "//xsi:Catalog/xsi:Url" and "//xsi:Catalog/Url" but none of them helps.

Any help would be greatly appreciated.

Thanks,
Rupinder

I think it is "//xsi:Url". Because of the // operator you don't have to specify the whole tree hierarchy.