Evaluate expression in XSLT

[SubasreeG]

Hi,

I have a situation where expression to evaluate comes from the user. I have to execute the expression and based upon the result i have to perform certain operation. The problem is that the expression given by the user (in the form of a variable) does not evaluate when i give it under the if element in xslt.

I have the sample code attached.

// the variable $condn is like this (this is an input from the user)
$condn=starts-with($obj,'PRJ.1411.DSG1.')
<xsl:choose>
           <xsl:when test="$condn">          
              <z:row>
                <xsl:for-each select="*">
                  <xsl:attribute name="{name(.)}">
                    <xsl:value-of select="."/>
                  </xsl:attribute>
                </xsl:for-each>
              </z:row>
            </xsl:when>
          </xsl:choose>

The problem is that the if statement evaluates to true always (the expression in the variable is not getting evaualted).
What can i do? I am not very familiar with XSLT.