parse the JSON output code example
Example 1: javascript parse json
const json = '{ "fruit": "pineapple", "fingers": 10 }';
const obj = JSON.parse(json);
console.log(obj.fruit, obj.fingers);
Example 2: json parse returns object
var str = '[{"UserName":"xxx","Rolename":"yyy"}]'; // your response in a string
var parsed = JSON.parse(str); // an *array* that contains the user
var user = parsed[0]; // a simple user
console.log(user.UserName); // you'll get xxx
console.log(user.Rolename); // you'll get yyy