How to parse Authorize.net payment response in Ionic / JavaScript?

Ionic Framework
1

I am getting a response from authorize.net payment gateway and tried many times and many ways to parse it but no luck.

Here is a response:

"{"transactionResponse":{"responseCode":"1","authCode":"XXXXXX","avsResultCode":"Y","cvvResultCode":"P","cavvResultCode":"2","transId":"11111111111","refTransID":"","transHash":"","testRequest":"0","accountNumber":"XXXX0002","accountType":"AmericanExpress","messages":[{"code":"1","description":"This transaction has been approved."}],"transHashSha2":"2E6533BDC93C975EE3C1134B7421A337D5B8FB9C257437DB8B4XXXX4BCD92024B33704B811C69E58527359CA8628E8E33E55AA68B881E6F3D15B5F2FEAEB490B","SupplementalDataQualificationIndicator":0,"networkTransId":"HLH5UGDQFZ98LHRLDGIZEG7"},"messages":{"resultCode":"Ok","message":[{"code":"I00001","text":"Successful."}]}}"

I am following this tutorial.

I have tried this:

const result = JSON.parse(JSON.stringify(res.response));
console.log('1', result);

And result is:

1 {"transactionResponse":{"responseCode":"1","authCode":"9UQISS","avsResultCode":"Y","cvvResultCode":"P","cavvResultCode":"2","transId":"60164579108","refTransID":"","transHash":"","testRequest":"0","accountNumber":"XXXX0002","accountType":"AmericanExpress","messages":[{"code":"1","description":"This transaction has been approved."}],"transHashSha2":"2E6533BDC93C975EE3C1134B7421A337D5B8FB9C257437DB8B4DA924BCD92024B33704B811C69E58527359CA8628E8E33E55AA68B881E6F3D15B5F2FEAEB490B","SupplementalDataQualificationIndicator":0,"networkTransId":"HLH5UGDQFZ98LHRLDGIZEG7"},"messages":{"resultCode":"Ok","message":[{"code":"I00001","text":"Successful."}]}}

I want result like this:

{
  "transactionResponse": {
    "responseCode": "1",
    "authCode": "XXXXXX",
    "avsResultCode": "Y",
    "cvvResultCode": "P",
    "cavvResultCode": "2",
    "transId": "11111111111",
    "refTransID": "",
    "transHash": "",
    "testRequest": "0",
    "accountNumber": "XXXX0002",
    "accountType": "AmericanExpress",
    "messages": [
      {
        "code": "1",
        "description": "This transaction has been approved."
      }
    ],
    "transHashSha2": "2E6533BDC93C975EE3C1134B7421A337D5B8FB9C257437DB8B4XXXX4BCD92024B33704B811C69E58527359CA8628E8E33E55AA68B881E6F3D15B5F2FEAEB490B",
    "SupplementalDataQualificationIndicator": 0,
    "networkTransId": "HLH5UGDQFZ98LHRLDGIZEG7"
  },
  "messages": {
    "resultCode": "Ok",
    "message": [
      {
        "code": "I00001",
        "text": "Successful."
      }
    ]
  }
}

Please guide me…