Need help pasrsing api response

Hi all,

I'm new to testcomplete and I'm assigned to write test scripts using jscript for some API testing. For one of the test, I need to parse JSON response and retrive a key of some sort and save it. I can't seems to wrap my hand around it and figure it out. Any help would be appreciated.

Following is API response -

{
"date":"2016-12-31T00:00:00.0000000",
"accountid":"8675309",,
"license_mode":"mode1",
"user_email":"primaryuser@gmail.com",
"key":"0efca74a-7f9b-41f8-96a9-b05a3367854a",
}

and I need to retrive the key and save it for later use.

function Get_Key (responsetxt)
{
  var name = "key"
  var qs = dotNET.System_Web.HttpUtility.ParseQueryString(responsetext);
  var strValue = qs.Item(name).OleValue;
}

that's all I have so far.

Thank you very much for taking time out to help me.