JavaScript

DNS Query MX Records

Shows how to perform a DNS query to retrieve MX records.

Note: This example requires Chilkat v9.5.0.96 or later.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

JavaScript

var success = false;

var dns = new CkDns();

var json = new CkJsonObject();
json.EmitCompact = false;

success = dns.Query("MX","somebody@gmail.com",json);
if (success == false) {
    console.log(dns.LastErrorText);
    return;
}

console.log(json.Emit());

// Sample response.
// Parsing code below..

// -------------------------------------------------------------------------------
// Note: Chilkat will return the results sorted by "pref" from lowest to highest.
// -------------------------------------------------------------------------------

// {
//   "answer": {
//     "mx": [
//       {
//         "name": "gmail.com",
//         "ttl": 491,
//         "pref": 5,
//         "domain": "gmail-smtp-in.l.google.com"
//       },
//       {
//         "name": "gmail.com",
//         "ttl": 491,
//         "pref": 10,
//         "domain": "alt1.gmail-smtp-in.l.google.com"
//       },
//       {
//         "name": "gmail.com",
//         "ttl": 491,
//         "pref": 20,
//         "domain": "alt2.gmail-smtp-in.l.google.com"
//       },
//       {
//         "name": "gmail.com",
//         "ttl": 491,
//         "pref": 30,
//         "domain": "alt3.gmail-smtp-in.l.google.com"
//       },
//       {
//         "name": "gmail.com",
//         "ttl": 491,
//         "pref": 40,
//         "domain": "alt4.gmail-smtp-in.l.google.com"
//       }
//     ]
//   }
// }

// Use this online tool to generate parsing code from sample JSON: 
// Generate Parsing Code from JSON

var name;
var ttl;
var pref;
var domain;

var i = 0;
var count_i = json.SizeOfArray("answer.mx");
while (i < count_i) {
    json.I = i;
    name = json.StringOf("answer.mx[i].name");
    ttl = json.IntOf("answer.mx[i].ttl");
    pref = json.IntOf("answer.mx[i].pref");
    domain = json.StringOf("answer.mx[i].domain");
    i = i+1;
}