if, else, elseif – knowledgebase JJ

The use of if, elseif and else directives to conditionally skip a section of the template. The condition-s must evaluate to a boolean value, or else an error will abort template processing. The elseif-s and else-s must occur inside if (that is, between the if start-tag and end-tag). The if can contain any number of elseif-s (including 0) and at the end optionally one else.

Synopsis

<#if condition>
…
<#elseif condition2>
…
<#elseif condition3>
…
…
<#else>
…
</#if>

Examples

if with 0 elseif and no else:

<#if x == 1>
  x is 1
</#if>

if with 0 elseif and else:

<#if x == 1>
  x is 1
<#else>
  x is not 1
</#if>

if with elseif and no else:

<#if x == 1>
  x is 1
<#elseif x == 2>
  x is 2
</#if>

if with 2 elseif and else:

<#if x == 1>
  x is 1
<#elseif x == 2>
  x is 2
<#elseif x == 3>
  x is 3
<#else>
  x is not 1 nor 2 nor 3
</#if>

nest if directives

<#if x == 1>
  x is 1
  <#if y == 1>
    and y is 1 too
  <#else>
    but y is not
  </#if>
<#else>
  x is not 1
  <#if y < 0>
    and y is less than 0
  </#if>
</#if>

Note:

Check if x > 0 or x >= 0,

writing <#if x > 0> and <#if x >= 0> is WRONG, as the first > will close the #if tag. To work that around, write <#if x > 0> or <#if &gte; 0>.

Also note that if the comparison occurs inside parentheses, you will have no such problem, like <#if foo.bar(x > 0)> works as expected.