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DocsRoxenWebServer 6.1Web Developer ManualIf Tags
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<if accept>
<if client>
<if clientvar>
<if config>
<if cookie>
<if date>
<if defined>
<if domain>
<if exists>
<if expr>
<if false>
<if group>
<if internal-exists>
<if ip>
<if kerberos-auth>
<if language>
<if match>
<if Match>
<if module>
<if pragma>
<if prestate>
<if recaptcha-verify>
<if referrer>
<if scope>
<if sizeof>
<if supports>
<if time>
<if true>
<if type-from-data>
<if type-from-filename>
<if user>
<if variable>
<if Variable>
<if variable-exists>

<if variable-exists></if>

Provided by module: Tags: RXML tags

Does the given variable exist? I.e. is it bound to any value, be it null or something else?

The difference from the <if variable> plugin is that this one returns true for variables with a null value (typically produced by the <emit source="sql"> for columns containing an SQL NULL value).

Compatibility note: When the compatibility level is 4.5 or lower, <emit source="sql"> assigns the undefined value for SQL NULLs instead of a proper null value. This test is therefore false for such values too unless the compatibility level is higher than 4.5.



Name of the variable to test.