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.NET Core C#

HTTPS multipart/form-data POST

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Demonstrates how to send a multipart/form-data POST over HTTPS (using TLS).

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

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

// This example demonstrates how to send a multipart/form-data POST that
// looks like this:

// 	POST /cgi/XXX.pl HTTP/1.0
// 	Accept: text/html
// 	Connection: Keep-Alive
// 	User-Agent: XXX/8.0.15
// 	Content-type: multipart/form-data, boundary=XXXxyxy
// 	Content-Length: 682
// 
// 	--XXXxyxy
// 	content-disposition: form-data; name="UploadAgent"
// 
// 	InterfaceVersion1.5
// 	--XXXxyxy
// 	content-disposition: form-data; name="user"
// 
// 	userValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="password"
// 
// 	passwordValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="file"
// 
// 	fileValue
// 	--XXXxyxy
// 	content-disposition: form-data; name="data_version"
// 
// 	dataVersion
// 	--XXXxyxy
// 	content-disposition: form-data; name="content2"; filename="XXX"
// 
// 	THE FILE CONTENT GOES HERE...
// 	--XXXxyxy--
// 

// First, let's build the HTTP request object
Chilkat.HttpRequest req = new Chilkat.HttpRequest();

req.HttpVerb = "POST";
req.Path = "/cgi/XXX.pl";

// The boundary string is automatically generated and added by Chilkat.
// The value for the boundary string doesn't matter. (As long as it's a unique string that doesn't occur elsewhere in the request.)
req.ContentType = "multipart/form-data";

// Adding the Connection: Keep-Alive is optional.  It only makes sense if the intent is to send
// additional requests to the same domain (your-namespace-sb.accesscontrol.windows.net) within a reasonable time period.
req.AddHeader("Connection","Keep-Alive");

// --------------------------------------------------
// IMPORTANT: Never set the Content-Length header.  
// Chilkat will automatically compute the correct Content-Length and will add it.
// --------------------------------------------------

// If a specific User-Agent header field is needed, it can be added by calling AddHeader.
req.AddHeader("User-Agent","XXX/8.0.15");

// The "Accept" header, if present, tells the server what Content-Type responses will be accepted.
// In this case, we're telling the server that we'll only accept "text/html" responses, and therefore
// the server SHOULD only send a text/html response.  Technically, the Accept header is not required.
req.AddHeader("Accept","text/html");

// Add the params to the request.  Given that the Content-Type is set to "multipart/form-data", when
// Chilkat composes the request, it will put each param in it's own MIME sub-part (i.e. in it's own
// part delimited by the boundary string).
req.AddParam("UploadAgent","InterfaceVersion1.5");
req.AddParam("user","userValue");
req.AddParam("password","passwordValue");
req.AddParam("file","fileValue");
req.AddParam("data_version","dataVersion");

// The last param is the contents of a file.
// If it's a file on disk, we can add it like this:
string pathToFileOnDisk = "c:/someDir/someFile.dat";
success = req.AddFileForUpload("content2",pathToFileOnDisk);
if (success == false) {
    Debug.WriteLine(req.LastErrorText);
    return;
}

// Alternatively, if the contents of the file are in memory, perhaps in a string
// variable, the file can be added like this instead.
string fileContents = "This is the content of the file being uploaded.";
success = req.AddStringForUpload("content2","XXX",fileContents,"utf-8");

// -----------------------------------------------------------
// IMPORTANT: To duplicate the HTTP request shown above, you'll want to choose 
// either AddStringForUpload or AddFileForUpload, but not both.  It's possible to upload
// any number of files by calling AddStringForUpload and/or AddFileForUpload any number
// of times, once per file to be uploaded.  This of course assumes that the receiving
// end is programmed to receive multiple files..
// ------------------------------------------------------------

Chilkat.Http http = new Chilkat.Http();

// The request is ready... now send it using HTTPS (which is port 443 by default).

Chilkat.HttpResponse resp = new Chilkat.HttpResponse();
success = http.HttpSReq("www.myserver.com",443,true,req,resp);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

Debug.WriteLine("HTTP response status: " + Convert.ToString(resp.StatusCode));

// In this case, the response would be HTML because our Accept header
// told the server to only return HTML.  The HTML is available on the BodyStr
// property of the response object:
string htmlStr = resp.BodyStr;
Debug.WriteLine("Received:");
Debug.WriteLine(htmlStr);