Split XML file based on first character of a string

I would like to split a file in to several files based on the starting letter of an element. For example:

 <Employees>      
 <Employee id="1"> 
 <firstname value="Atif"></firstname>           
 <lastname value="Bashir"></lastname>           
 <age >32</age>           
 </Employee>      
 <Employee id="2"> 
 <firstname value="xyz"></firstname>           
 <lastname value="abc"></lastname>           
 <age >32</age>           
 </Employee>      
 <Employee id="3"> 
 <firstname value="abc"></firstname>           
 <lastname value="none"></lastname>           
 <age >32</age>           
 </Employee>      
 </Employees> 

After applying transformation, the above file should be split into two files because the first character of Employee/firstname[@value] (and group all the data). So for above case first file should be:

a.xml

 <Employees>      
 <Employee id="1"> 
 <firstname value="Atif"></firstname>           
 <lastname value="Bashir"></lastname>           
 <age >32</age>           
 </Employee>      
 <Employee id="3"> 
 <firstname value="abc"></firstname>           
 <lastname value="none"></lastname>           
 <age >32</age>           
 </Employee>      
 </Employees> 

and the second file should be:

x.xml

 <Employees>      
 <Employee id="2"> 
 <firstname value="xyz"></firstname>           
 <lastname value="abc"></lastname>           
 <age >32</age>           
 </Employee>      
 </Employees>      

What is the XSLT code to perform this transformation?

Than开发者_Go百科k you!

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With XSLT 2.0:

<xsl:for-each-group select="Employee" 
                    group-by="lower-case(substring(firstname,1,1))">
  <xsl:result-document href="{current-grouping-key()}.xml">
    <xsl:copy-of select="current-group()"/>
  </xsl:result-document>
</xsl:for-each-group>

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If you are using XSLT 2.0, look into <xsl:result-document>.

If you are using XSLT 1.0, you need an extension element, such as <exsl:document>.

More clues:

• Using XSLT to output multiple files
• Does libxslt have a feature for splitting a document into multiple documents?