Fiddler Ideas

The free web debugging proxy for any browser, system or platform.

How to call JSON methods inside fiddler script?

Hi there, what's the correct way to call:

 

JSON.stringify({});

JSON.parse("{}");

 

after calling these JSON methods, fiddler says:

Variable 'JSON' has not been declared

 

cheers,

David

 

  • David Henrry Ticona
  • Nov 21 2017
  • Needs review
Bug
  • Attach files
  • Eric Lawrence commented
    November 21, 2017 22:54

    The JSON object you're trying to use is a part of the browser's Document Object model and doesn't directly exist within FiddlerScript. The .NET framework (on which FiddlerScript runs) offers a variety of JSON libraries and one of them may be your best choice.

    Having said that, Fiddler does itself have its own JSON objects; they're not optimized for FiddlerScript, however, so you might find them a little cumbersome. At the top of your script, add: 

     
       using Fiddler.WebFormats;
     
    In the code, add e.g.
     
    var oResponseBody = oSession.GetResponseBodyAsString();
    JSON.JSONParseResult oJSON = JSON.JsonDecode(oResponseBody) as JSON.JSONParseResult;
    Hashtable oObj = oJSON.JSONObject as Hashtable; 
    var oVal = (oObj != null) ? oObj["myObjectValue"] : null;