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Your LimeSurvey version: 5.3.32+220817
Own server or LimeSurvey hosting: Own Server
Survey theme/template: Fruity (Modified)
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What I would like to know is this .. is it possible to set the LANG / SURVEYLANGUAGE variable based on the answer to a question?

I know it is possible to set the answer to a question based on these variables ... for example {Country=if(SURVEYLANGUAGE=='en',1,if(SURVEYLANGUAGE=='de',2,3))} in an equation question, but what I would like to do is reverse this to set the survey language based on the answer of a question.

Thanks in advance

Dave

No, the survey language is not a question so you cannot programmatically set it with ExpressionScript.

I'm not sure why you would want to since it is an indication of what language the survey was seen in.

Thanks Tony

I wasn't sure if you could set the variable outside of the Lang= URL variable but you have confirmed this.

The reason I was asking is that the client wants a clean URL with only numerical variable values ... I don't know why and I didn't ask.

I will create a redirect PHP page to meet their needs

Thanks
Dave

I don't know why and I didn't ask.

Yeah, sometimes that is better...

What you could do is have a short survey with just a question about the language and then use the END URL feature to automatically redirect them to the correct language version of the "real" survey.