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Your LimeSurvey version: url=https://itasmcda.limesurvey.net/surveyAdministration/listsurveys#modalSystemInformation]Version 5.6.4[/url
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Hi,
I want to retrieve the survey responses (Json format or CSV file) corresponding to each participant.
1)  The Export_responses method gives a base 64 encoded string. How to convert this response to Json format? Or is it possible to export to CSV file?
I am coding in Java. Below is the snippet from postman:
{
 "method": "export_responses",
 "params": [
   "session_key",
   "survey_id",
    "json", 
    null, 
    "all", 
    null, 
    null
 ],
 "id": 2
}

2) Also, when I am trying to get the question list from the survey, the response is not proper although the status is (200 OK).
Below is the method i am using to send request:
{
 "method": "list_questions",
 "params": [
   "session_key",
   "survey_id",
        null,
        null
 ],
 "id": 2
}

Note: api.limesurvey.org/classes/remotecontrol_handle.html is used to implement methods in the above case.

Thanks in advance!

1) This is a Java question, not a LimeSurvey question - www.google.com/search?client=firefox-b-d&q=java+decode+base64

2) What do you mean by "the response is not proper"?

hank you for the reply!
Below is the response for the method list_questions as mentioned above.