Dart

HTTP Request Boundary Property

Explains and demonstrates the HTTP request Boundary property. For multipart HTTP requests, Chilkat auto-generates a boundary string when the Boundary property is left unset (or empty). For example:

POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=------------090207000006060206010508
Host: domain
Content-Length: 378

--------------090207000006060206010508
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--------------090207000006060206010508
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--------------090207000006060206010508--

If the Boundary property is set, then Chilkat uses it. For example, if the Boundary property is set to "ABC123HELLOWORLD"

POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=ABC123HELLOWORLD
Host: domain
Content-Length: 318

--ABC123HELLOWORLD
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--ABC123HELLOWORLD
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--ABC123HELLOWORLD--

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  final req = CkHttpRequest();

  req.httpVerb = 'POST';
  req.path = '/something';
  req.contentType = 'multipart/form-data';

  req.addStringForUpload('fileA', 'fileA.txt', 'This is the contents of file A', 'utf-8');
  req.addStringForUpload('fileB', 'fileB.txt', 'This is the contents of file B', 'utf-8');

  // When the Boundary property is empty (has not yet been set)
  // Chilkat auto-generates a random boundary for the request.
  // This should almost always be sufficient.
  // For example, one can see the generated boundary here:
  print(req.generateRequestText());

  // If the Boundary property is set to a specific string, then the
  // request will use it:
  req.boundary = 'ABC123HELLOWORLD';
  print(req.generateRequestText());
}