Passing a variable from study to study in JATOS via URL

Comments

• sebastiaan

  May 5 edited May 5

  Hi @marko ,

  If the experiment is hosted on a JATOS server, URL parameters are available in jaros.urlQueryParameters . If the experiment is running as a standalone HTML file (e.g. during testing), the parameter is available through the URLSearchParams class.

  The example below shows how you can get the task URL parameter in a way that works both when running the experiment through JATOS and when running it standalone. (The script assumes that task is a number.)

  // Check if the task was passed a url parameter through JATOS
  if ((typeof jatos !== 'undefined') && ('task' in jatos.urlQueryParameters)) {
      task = Number(jatos.urlQueryParameters['task'])
      console.log(`task ${task} was specified as a JATOS URL query`)
  // Else check if it was passed as a regular parameter (for testing)
  // and fall back to 0 if no parameter was specified.
  } else {
      const urlParams = new URLSearchParams(window.location.search)
      task = Number(urlParams.get('task') || 0)
      if (task === 0) {
          console.log('no task was specified')
      } else {
          console.log(`task ${task} was specified as a regular URL query`)
      }
  }
  

  Hope this helps!

  — Sebastiaan

  
  
  Check out SigmundAI.eu for our OpenSesame AI assistant!
  
• kri

  May 6

  I agree with Sebastian and just want to answer your second question: how to write it in the results of the second study: Use on of the functions jatos.submitResultData or jatos.appendResultData.

  Best,

  Kristian
• mmalikovic

  May 7

  Dear Sebastian and Kristian,

  Thank you for the answer. Now I see that I have another related question: How can I insert the value of some variable from the first experiment into the URL. So, if in the first experiment I generate the value of the variable "idisp", how can I transfer the value of that variable through the URL to the next experiment. Experiments are linked in JATOS via the "End Redirect URL" option.

  Thank you again,

  Marko
• kri

  May 16

  Hi Marko,

  Somehow your second question got lost. It's better to start a new question in the forum so this doesn't happen and also so other people can find it easier.

  You would use jatos.endStudyAndRedirect to end your study, redirect it to a different page and pass on information via the URL query parameters. The "End Redirect URL" option in the study properties does the same but I guess you want to pass a parameter that only exists in your code.

  Here is an example

  1. You'd get a study link to your second study, e.g. https://www.example.com/base/publix/Hbr4mxMnyjt. You probably have to use a type 'general' study link, because it's difficult to use individual links in this scenario.
  2. Add the URL query parameter to it, e.g. if your parameter is myParameter=1234ABCD you'd have the URL https://www.example.com/base/publix/Hbr4mxMnyjt?myParameter=1234ABCD .
  3. Then use jatos.endStudyAndRedirect in your first study to redirect to your second study:

  jatos.endStudyAndRedirect("https://www.example.com/publix/Hbr4mxMnyjt?myParameter=1234ABCD");
  

  You can pass on as many parameters as you want, just separate them by '&'.

  Best,

  Kristian