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.NET Core C#

HTTP multipart/form-data Upload

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Demonstrates how to upload files to an HTTP server using a multipart/form-data POST.

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

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

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

Chilkat.HttpRequest req = new Chilkat.HttpRequest();
req.HttpVerb = "POST";
req.ContentType = "multipart/form-data";
req.Path = "rcvFormDataUpload.aspx";

// Send an "Expect: 100-continue" header in the request.
// This causes the HTTP server to end a 100-continue response
// immediately after receiving the HTTP header.  The client
// (Chilkat) will receive this intermediate response, and if
// it's not an error response, it knows that the HTTP server will
// accept the data that is forthcoming.
// The alternative is to get an error response after trying to upload
// the entire contents of the files.
req.AddHeader("Expect","100-continue");

// Call AddFileForUpload2 for each file to be uploaded in the HTTP multipart/form-data POST
// To allow Chilkat to determine the content-type automatically based on file-extension,
// call AddFileForUpload instead.

// The 1st arg is the filename passed in the HTTP request.
// The 2nd arg is the path in the local filesytem.
// The file is not loaded into memory.  It is streamed directly from the file
// when the HTTP POST is sent.
success = req.AddFileForUpload2("starfish.jpg","c:/qa_data/starfish.jpg","image/jpg");
if (success == false) {
    Debug.WriteLine(req.LastErrorText);
    return;
}

success = req.AddFileForUpload("something.pdf","c:/qa_data/something.pdf");
if (success == false) {
    Debug.WriteLine(req.LastErrorText);
    return;
}

// Its also possible to add a file from a string:
success = req.AddStringForUpload("test.xml","test.xml","<abc>This is the test.xml content</abc>","utf-8");
// We'll assume success since no files are involved..

// This sends the HTTP request (with 3 files being uploaded) to
// http://www.mywebserver123abc.com/rcvFormDataUpload.aspx
Chilkat.HttpResponse resp = new Chilkat.HttpResponse();
success = http.HttpSReq("www.mywebserver123abc.com",80,false,req,resp);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

Debug.WriteLine("HTTP response status: " + Convert.ToString(resp.StatusCode));
// See the online reference documentation for 
// other information that can be obtained from the response object.

// To send using SSL/TLS, do this instead.
// This sends to https://www.mywebserver123abc.com/rcvFormDataUpload.aspx
success = http.HttpSReq("www.mywebserver123abc.com",443,true,req,resp);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

Debug.WriteLine("HTTP response status: " + Convert.ToString(resp.StatusCode));
// See the online reference documentation for 
// other information that can be obtained from the response object.