(Delphi DLL) DNS Query TXT Records

See more DNS Examples

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

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

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Dns, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
dns: HCkDns;
json: HCkJsonObject;
success: Boolean;
name: PWideChar;
ttl: Integer;
text: PWideChar;
i: Integer;
count_i: Integer;

begin
dns := CkDns_Create();

json := CkJsonObject_Create();
CkJsonObject_putEmitCompact(json,False);

success := CkDns_Query(dns,'TXT','x.com',json);
if (success = False) then
  begin
    Memo1.Lines.Add(CkDns__lastErrorText(dns));
    Exit;
  end;

Memo1.Lines.Add(CkJsonObject__emit(json));

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

// {
//   "answer": {
//     "txt": [
//       {
//         "name": "x.com",
//         "ttl": 300,
//         "text": "kkdl3qb3tcrmdhfsm803p67r0my0svs8"
//       },
//       {
//         "name": "x.com",
//         "ttl": 300,
//         "text": "v=spf1 ip4:199.16.156.128/26 ip4:199.59.150.64/26 include:_spf.google.com include:spf-008d0a01.pphosted.com -all"
//       },
//       {
//         "name": "x.com",
//         "ttl": 300,
//         "text": "google-site-verification=8yQmoVhQedzlt36RPeQP41ytrEFk9aHEnde_xm0626g"
//       },
//       {
//         "name": "x.com",
//         "ttl": 300,
//         "text": "google-site-verification=F6u9mGL--d2lbLljvH3b1UUgXtevQPdcamKr9c8914A"
//       }
//     ]
//   }
// }

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

i := 0;
count_i := CkJsonObject_SizeOfArray(json,'answer.txt');
while i < count_i do
  begin
    CkJsonObject_putI(json,i);
    name := CkJsonObject__stringOf(json,'answer.txt[i].name');
    ttl := CkJsonObject_IntOf(json,'answer.txt[i].ttl');
    text := CkJsonObject__stringOf(json,'answer.txt[i].text');
    i := i + 1;
  end;

CkDns_Dispose(dns);
CkJsonObject_Dispose(json);

end;