(C#) MX Lookup Mail Server Domain by Email Address

How to find the mail server for a given email address. Returns the domain name of the primary mail server.

Note: This example requires Chilkat v11.0.0 or greater.

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bool success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Dns dns = new Chilkat.Dns();
Chilkat.JsonObject json = new Chilkat.JsonObject();

string emailAddr = "bob@example.com";

// This gets all MX domains for an email address.  (Typically one domain.)
// The preferred domain will be at index 0 (see below).
success = dns.Query("MX",emailAddr,json);
if (success == false) {
    Debug.WriteLine(dns.LastErrorText);
    return;
}

int i = 0;
int count_i = json.SizeOfArray("answer.mx");
while (i < count_i) {
    json.I = i;
    string domain = json.StringOf("answer.mx[i].domain");
    Debug.WriteLine(domain);
    i = i + 1;
}