Why do I get this error (This document already has a 'DocumentElement' node)
Question
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I am new to using asp.net, and I am chashing and buring at step 1
What I am trying to do is to server up xml data in a web form, which I thought would be pretty straight forward.
Here is the layout of the xml data:
<?xml version="1.0" encoding="utf-8" ?>
<?xml-stylesheet type="text/xsl" href="test1.xsl"?>
<catalog>
<childelmt>
<grandchildelmt1>text</grandchildelmt1>
<grandchildelmt2>text</grandchildelmt2>
<grandchildelmt3>text</grandchildelmt3>
<grandchildelmt4>text</grandchildelmt4>
<grandchildelmt5>text</grandchildelmt6>
<grandchildelmt6>text</grandchildelmt6>
...
<grandchildelmtX>text</grandchildelmtX>
</childelmt><childelmt>
<grandchildelmt1>text</grandchildelmt1>
<grandchildelmt2>text</grandchildelmt2>
<grandchildelmt3>text</grandchildelmt3>
<grandchildelmt4>text</grandchildelmt4>
<grandchildelmt5>text</grandchildelmt6>
<grandchildelmt6>text</grandchildelmt6>
...
<grandchildelmtX>text</grandchildelmtX>
</childelmt><childelmt>
<grandchildelmt1>text</grandchildelmt1>
<grandchildelmt2>text</grandchildelmt2>
<grandchildelmt3>text</grandchildelmt3>
<grandchildelmt4>text</grandchildelmt4>
<grandchildelmt5>text</grandchildelmt6>
<grandchildelmt6>text</grandchildelmt6>
...
<grandchildelmtX>text</grandchildelmtX>
</childelmt>...
...
...<childelmt>
<grandchildelmt1>text</grandchildelmt1>
<grandchildelmt2>text</grandchildelmt2>
<grandchildelmt3>text</grandchildelmt3>
<grandchildelmt4>text</grandchildelmt4>
<grandchildelmt5>text</grandchildelmt6>
<grandchildelmt6>text</grandchildelmt6>
...
<grandchildelmtX>text</grandchildelmtX>
</childelmt></catalog>
Here is the test1.xsl file that is referenced
<?xml version="1.0" encoding="utf-8" ?>
<!-- File Name: test1.xsl -->
<xsl
tylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:fo="http://www.w3.org/2005/02/xpath-functions">
<xsl:template match="/">
<h2>Page Title</h2>
<xsl:variable name="test2" select="catalog/childelmt[grandchildelmtY='text']"/>
<table border="1" cellpadding="5">
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt1"/></td>
</xsl:for-each>
</tr>
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt2"/></td>
</xsl:for-each>
</tr>
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt3"/></td>
</xsl:for-each>
</tr>
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt4"/></td>
</xsl:for-each>
</tr>
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt5"/></td>
</xsl:for-each>
</tr>
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmt6"/></td>
</xsl:for-each>
</tr>.....
.....
.....
.....
<tr>
<td>Row Heading</td>
<xsl:for-each select="$test2">
<td><xsl:value-of select="grandchildelmtX"/></td>
</xsl:for-each>
</tr>
</table></xsl:template>
</xsltylesheet>
What this stylesheet does is get data from each node and lay it out by rows instead of columns. If I display the xml file in a browser, the page is rendered as I would like.
I followed the walktrhough document "Creating a web page to display XML data, located at -- http://msdn2.microsoft.com/en-us/library/13ftcwy9(VS.80).aspx and I can get it work with the data provided in the example, but I can't get this concept to work with my data.
What I get when I try to render the aspx page is the criptic asp error (see below) which is greek to me. I have missed something somewhere, I just can't figure out what it is.
Help Please!
Server Error in '/test' Application.
This document already has a 'DocumentElement' node.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.InvalidOperationException: This document already has a 'DocumentElement' node.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[InvalidOperationException: This document already has a 'DocumentElement' node.] System.Xml.XmlDocument.IsValidChildType(XmlNodeType type) +1891757 System.Xml.XmlDocument.AppendChildForLoad(XmlNode newChild, XmlDocument doc) +25 System.Xml.XmlLoader.LoadDocSequence(XmlDocument parentDoc) +20 System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean preserveWhitespace) +162 System.Xml.XmlDocument.Load(XmlReader reader) +96 System.Web.UI.WebControls.XmlDataSource.PopulateXmlDocument(XmlDocument document, CacheDependency& dataCacheDependency, CacheDependency& transformCacheDependency) +305 System.Web.UI.WebControls.XmlDataSource.GetXmlDocument() +154 System.Web.UI.WebControls.XmlDataSourceView.ExecuteSelect(DataSourceSelectArguments arguments) +24 System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback) +17 System.Web.UI.WebControls.DataBoundControl.PerformSelect() +149 System.Web.UI.WebControls.BaseDataBoundControl.DataBind() +70 System.Web.UI.WebControls.GridView.DataBind() +4 System.Web.UI.WebControls.BaseDataBoundControl.EnsureDataBound() +82 System.Web.UI.WebControls.CompositeDataBoundControl.CreateChildControls() +69 System.Web.UI.Control.EnsureChildControls() +87 System.Web.UI.Control.PreRenderRecursiveInternal() +41 System.Web.UI.Control.PreRenderRecursiveInternal() +161 System.Web.UI.Control.PreRenderRecursiveInternal() +161 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1360
Version Information: Microsoft .NET Framework Version:2.0.50727.312; ASP.NET Version:2.0.50727.312
