xsl:for-each-group help needed

问题:

I went through XSLT Grouping Examples and Using for-each-group for high performance XSLT . I have a problem with for-each-group.

My XML

Introduction
    
XSLT and XQuery
    
XSLT
    
        XSLT is used to write stylesheets.
    
XQuery
    
        XQuery is used to query XML databases.
    
XQuery and stylesheets
    
        XQuery is used to query XML databases.
    
XSLT and XQuery
    
XSLT
  

My Wanted Output

Introduction
    
       
 XSLT and XQuery 
       
          
XSLT
          
             XSLT is used to write stylesheets.             
              
          
 XQuery is used to query XML databases              
          
             
 XQuery is used to query XML databases.
                    
             
XQuery and stylesheets
             
           XQuery is used to query XML databases.
                   
             
XSLT and XQuery
        
                
XSLT
           

I tried with this. (not working)

Will someone show me the correct way to get my wanted result?

回答1:

Here is an XSLT 2.0 stylesheet using for-each-group in a recursive function (I prefer that to a named template with XSLT 2.0):

When I apply that stylesheet with Saxon 9 to the input

    
Introduction
    
XSLT and XQuery
    
XSLT
    
        XSLT is used to write stylesheets.
    
XQuery
    
        XQuery is used to query XML databases.
    
XQuery and stylesheets
    
        XQuery is used to query XML databases.
    
XSLT and XQuery
    
XSLT
  

I get the result

    
Introduction
    
       
XSLT and XQuery
       
          
XSLT
          
               XSLT is used to write stylesheets.
              
          
XQuery
          
               XQuery is used to query XML databases.
          
             
XQuery and stylesheets
             
                  XQuery is used to query XML databases.
                         
       
XSLT and XQuery
       
          
XSLT
             

回答2:

This transformation uses keys and handles h1-title to h6-title:

When applied on this XML document (corrected the provided one and usin uniform values for the name attribute):

         
Introduction
         
XSLT and XQuery
         
XSLT
         
                  XSLT is used to write stylesheets.
         
XQuery
         
                  XQuery is used to query XML databases.
         
XQuery and stylesheets
         
                  XQuery is used to query XML databases.
         
XSLT and XQuery
         
XSLT
  

the wanted, correct result is produced:

    
Introduction
    
       
XSLT and XQuery
       
          
XSLT
          
              XSLT is used to write stylesheets.
               
       
XQuery
       
           XQuery is used to query XML databases.
       
          
XQuery and stylesheets
          
              XQuery is used to query XML databases.
             
    
XSLT and XQuery
    
       
XSLT
      

Do note:

This transformation solves the main problem of generating the hierarchy. Only trivial changes are needed if it is required that the top level name attribute has the value "h-title".

If more hierarchy levels are necessary, this requires only mechanical adding the corresponding or clauses to the definition of the keys and appending the pipe-delimited string of all name attributes' values with the corresponding new strings.

Here I have adapted and re-used a solution that Jeni Tennison gave for a similar problem.

回答3:

Each of your grouping steps is taking the original set of elements as input, whereas you need each step to work on the groups produced by the previous grouping step. And there are lots of other errors too, for example h1-title is not an attribute name.

It needs to be something like this:

   
           ... similar logic for the next level ...         
         
 

You can nest that as deeply as you want depending how many levels you want to handle; or if you want to handle an indefinite number, you can put the code in a named template and make a recursive call to handle the next level. At the innermost level, leave out the xsl:choose and just do xsl:copy-of select="current-group().

(I just noticed the trailing spaces in the "name" attribute. If these really exist, you will need to include them in the comparison test, or do normalize-space() to get rid of them.)

文章来源: xsl:for-each-group help needed