XSL array variable?

[kclan]

Is there any implicit method to use array to store the attribute values of a specified element?
My task is to check if there is a previous value exists such that there could be different expressions for them. For example, my xml is like this:

<p>
<c id=1>A</c>
<c id=2 ref=1>B</c>
<c id=3>C</c>
<c id=4>D</c>
<c id=5 ref=3>E</c>
</p>

-When looping through the element node c, firstly add the id value 1 into the array and display A with a specified color, say red.
-Then add the array by 2 and check that 1 is already in the array, so display B with the same color of A, i.e. red.
-Then add the array by 3 and display C with another color, say blue.
-Then add the array by 4 and display D with another color, say green.
-Then add the array by 5 and check that 3 is alreay in the array, so display E with the same color of C, i.e. blue.

The final output should be like this:

<font color="red">A<font>
<font color="red">B<font>
<font color="blue">C<font>
<font color="green">D<font>
<font color="blue">E<font>

Can I use xsl to do a such task? Thankyou very much.

 

[jel]

No, xsl doesn't have arrays; the concept that comes closest is the node-set.
In your case however you don't need an array: you can always reconstruct the value you used before.
Here's an example:

  <xsl:template match="c">
      <tr>
         <td>
            <xsl:attribute name="bgcolor">
               <xsl:call-template name="color">
                  <xsl:with-param name="id">
                     <xsl:choose>
                        <xsl:when test="@ref">
                           <xsl:value-of select="@ref" />
                        </xsl:when>
                        <xsl:otherwise>
                           <xsl:value-of select="@id" />
                        </xsl:otherwise>
                     </xsl:choose>
                  </xsl:with-param>
               </xsl:call-template>
            </xsl:attribute>
            <xsl:value-of select="." />
         </td>
      </tr>
   </xsl:template>

   <xsl:template name="color">
      <xsl:param name="id" />
      <!-- number is: the count of pereceding nodes that don't have a ref-attribute -->
      <xsl:variable name="number" select="count(//c[@id=$id]/preceding-sibling::c[not (@ref)])" />

      <xsl:choose>
         <xsl:when test="$number=0">
            <xsl:value-of select="'RED'" />
         </xsl:when>
         <xsl:when test="$number=1">
            <xsl:value-of select="'BLUE'" />
         </xsl:when>
         <xsl:when test="$number=2">
            <xsl:value-of select="'GREEN'" />
         </xsl:when>
      </xsl:choose>

   </xsl:template>

 

[kclan]

Thankyou.

If I don't know how many pereceding nodes that don't have a ref-attribute, I seem need to predefine as many as hard coding color. Is there any flexible way to deal with a such color value?

 

[jel]

The xsl I posted counts the number of preceding nodes without ref, so all you have to do is add enough color-variables:

      <xsl:choose>
         <xsl:when test="$number=0">
            <xsl:value-of select="'RED'" />
         </xsl:when>
         <xsl:when test="$number=1">
            <xsl:value-of select="'BLUE'" />
         </xsl:when>
         <xsl:when test="$number=2">
            <xsl:value-of select="'GREEN'" />
         </xsl:when>
         <xsl:when test="$number=3">
            <xsl:value-of select="'SILVER'" />
         </xsl:when>
         <!-- ETC ETC -->
         <xsl:otherwise>
            <xsl:value-of select="'GREY'" />
         </xsl:otherwise>
      </xsl:choose>

Of course, you might also invent a formula, where you relate the percentage of blue, red and green to the value of $number.