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C#

Add Parameters to Multipart Form-Data POSTs

Parameters (name=value) can be added to multipart/form-data POSTs (such as for file uploads) by using the AddParam method. This example sends the following HTTP POST
POST /something HTTP/1.1
Content-Type: multipart/form-data; boundary=------------010201080703010401070605
Host: domain
Content-Length: 560

--------------010201080703010401070605
Content-Disposition: form-data; name="name"

Joe
--------------010201080703010401070605
Content-Disposition: form-data; name="age"

25
--------------010201080703010401070605
Content-Disposition: form-data; name="fileA"; filename="fileA.txt"
Content-Type: text/plain

This is the contents of file A
--------------010201080703010401070605
Content-Disposition: form-data; name="fileB"; filename="fileB.txt"
Content-Type: text/plain

This is the contents of file B
--------------010201080703010401070605--

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C#
Chilkat.HttpRequest req = new Chilkat.HttpRequest();

req.HttpVerb = "POST";
req.Path = "/something";
req.ContentType = "multipart/form-data";

req.AddParam("name","Joe");
req.AddParam("age","25");

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");

Debug.WriteLine(req.GenerateRequestText());