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Workarounds: Manipulating a survey at runtime using Javascript - LimeSurvey 3.0+

From LimeSurvey Manual

Revision as of 13:49, 24 May 2019 by Cdorin (talk | contribs)

Often you want to manipulate certain elements of a survey at runtime. The only solution without touching the source code is to use JavaScript or jQuery which is shipped with LimeSurvey. Here are some examples to hide and style elements, validate user input or do calculations at runtime.

Other workarounds can be found at


Please keep in mind that these workarounds are not official LimeSurvey extensions - they are solutions that users have created for themselves.
Therefore LimeSurvey can't offer guarantees or support for these solutions.
If you have questions, please contact the users that, thankfully, shared their solutions with the community.



Help.pngIf you would like to receive survey design support, please contact one of the authorized LimeSurvey partners listed here: https://limesurvey.com .


Note: Expression Manager (EM) may cause some of these work-arounds to fail. Any custom javascript included as a .js file will be fine. However, if you in-line your JavaScript code, you must make sure that you have a space after every opening (left) curly brace, and a space before every closing (right) curly brace. Otherwise, Expression Manager (EM) will think that the content between the curly braces is something it should parse and understand. I have fixed all of the work-arounds below that can be fixed (many did not follow those rules). However, some will continue to break. If a work-around contains a regular expression which contains curly braces (to indicate a range of repeats of a sub-expression), EM will try to process those curly braces, and thus break your regular expression. Strategies to continue to support that work-around functionality are discussed below.

How to add a javascript workaround solution to this Wiki page?

Well, this is pretty easy. Click the edit icon and create your own headline within the javascript section starting with "!". Then add a short note about the version you have used when creating your workaround, you can copy/paste this code snippet ''Tested with: (enter LimeSurvey version and maybe browser)''.

Finally it's imported to mark all your code with code tags, other wise you might break this page.

  • Start tag: <syntaxhighlight lang="php" enclose="div">
  • End tag: </syntaxhighlight>.

How to use Script (eg. JavaScript etc.) in LimeSurvey

Plugin addScriptToQuestion allow to use a simple textarea for easily adding javascript.

To use JavaScript within LimeSurvey, the XSS filter must be turned off and the code inserted in the source of a question or a group description.

  • Go to Global settings --> Security and set "Filter HTML for XSS" to "Off".
  • Add a new question
  • Edit the question and click the "Source" button in the editor toolbar:
  Editor 1.png
  • Enter your script after the question text:
  Editor 2.png
  • Save the question

A simple test to see if JavaScript is enabled is to echo an alert. Use this code:

<script type="text/javascript" charset="utf-8">
   alert("Test!");
</script>

It is a good practice to use the jQuery $(document).on('ready pjax:complete') event to prevent the code from executing until the page is fully loaded, it is especially needed when using the ajax-mode in the 3.0.0 and upper default templates:

<script type="text/javascript" charset="utf-8">
   $(document).on('ready pjax:complete',function() {
       alert("Test!");
   });
</script>

Usage of brackets ({ and })

Important.png
Caution when using brackets ({ and }) in scripts : Expression manager uses brackets ({ and }) to enclose expressions. If you have to use brackets in your JavaScript, you must add a space or line feed after the opening bracket ({) and before the closing bracket (})

Examples of usage of brackets

Expression Manager will try to parse this JavaScript:

<script type="text/javascript" charset="utf-8">
   $(function() {console.log('broken javascript');});
</script>

Adding line feed prevents Expression Manager from parsing

<script type="text/javascript" charset="utf-8">
   $(function() {
      console.log('Adding a line feed for javascript');
   });
</script>

Expression Manager will try to parse this JavaScript:

<script type="text/javascript" charset="utf-8">
   if(myvar==1) {console.log('broken javascript');};
</script>

Adding spaces inside the brackets prevents Expression Manager from parsing

<script type="text/javascript" charset="utf-8">
   if(myvar==1) { console.log('Adding a space for javascript'); };
</script>