Conditional statements in xsl

Question

I working on a site which some if/or statements in XSL and being a little unfamilar with the language i'm not certain how to accomplish:

if [condion one is met] or [condition two is met] then do [action] otherwise do [alternative action]

can anyone offer some examples?

Thanks in advance!

Answer 1

In this case you would have to use a xsl:choose. It's like using if/else with a final else.

<xsl:choose>
  <xsl:when test="condition one or condition two">
    <!-- action -->
  </xsl:when>
  <xsl:otherwise>
    <!-- alternative action -->
  </xsl:otherwise>
</xsl:choose>

Answer 2

XSL has an <xsl:if>, but you're probably looking more for a <xsl:choose> / <xsl:when> / <xsl:otherwise> sequence. Some examples here (near the bottom). Maybe:

<xsl:choose>
    <xsl:when test="[conditionOne] or [conditionTwo]">
        <!-- do [action] -->
    </xsl:when>
    <xsl:otherwise>
        <!-- do [alternative action] -->
    </xsl:otherwise>
</xsl:choose>

Answer 3

Conditionals in XSLT are either an unary "if":

<xsl:if test="some Boolean condition">
  <!-- "if" stuff (there is no "else" here) -->
</xsl:if>

or more like the switch statement of other languages:

<xsl:choose>
  <xsl:when test="some Boolean condition">
    <!-- "if" stuff -->
  </xsl:when>
  <xsl:otherwise>
    <!-- "else" stuff -->
  </xsl:otherwise>
</xsl:choose>

where there is room for as many <xsl:when>s as you like.

Every XPath expression can be evaluated as a Boolean according to a set of rules. These (for the most part) boil down to "if there is something -> true" / "if there is nothing -> false"

• the empty string is false
• 0 is false (so is NaN)
• the empty node set is false
• the result of false() is false
• every other literal value is true (most notably: 'false' is true)
• the result of expressions is evaluated with said rules (no surprise here)

Answer 4

The general if statement syntax is

<xsl:if test="expression">
  ...some output if the expression is true...
</xsl:if>

Not sure if XSL has the else condition but you should be able to test if true then test if false or the other way around.