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Unicode C

HTTPS multipart/form-data POST

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

Chilkat Unicode C Downloads

Unicode C
#include <C_CkHttpRequestW.h>
#include <C_CkHttpW.h>
#include <C_CkHttpResponseW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttpRequestW req;
    const wchar_t *pathToFileOnDisk;
    const wchar_t *fileContents;
    HCkHttpW http;
    HCkHttpResponseW resp;
    const wchar_t *htmlStr;

    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
    req = CkHttpRequestW_Create();

    CkHttpRequestW_putHttpVerb(req,L"POST");
    CkHttpRequestW_putPath(req,L"/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.)
    CkHttpRequestW_putContentType(req,L"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.
    CkHttpRequestW_AddHeader(req,L"Connection",L"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.
    CkHttpRequestW_AddHeader(req,L"User-Agent",L"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.
    CkHttpRequestW_AddHeader(req,L"Accept",L"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).
    CkHttpRequestW_AddParam(req,L"UploadAgent",L"InterfaceVersion1.5");
    CkHttpRequestW_AddParam(req,L"user",L"userValue");
    CkHttpRequestW_AddParam(req,L"password",L"passwordValue");
    CkHttpRequestW_AddParam(req,L"file",L"fileValue");
    CkHttpRequestW_AddParam(req,L"data_version",L"dataVersion");

    // The last param is the contents of a file.
    // If it's a file on disk, we can add it like this:
    pathToFileOnDisk = L"c:/someDir/someFile.dat";
    success = CkHttpRequestW_AddFileForUpload(req,L"content2",pathToFileOnDisk);
    if (success == FALSE) {
        wprintf(L"%s\n",CkHttpRequestW_lastErrorText(req));
        CkHttpRequestW_Dispose(req);
        return;
    }

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

    http = CkHttpW_Create();

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

    resp = CkHttpResponseW_Create();
    success = CkHttpW_HttpSReq(http,L"www.myserver.com",443,TRUE,req,resp);
    if (success == FALSE) {
        wprintf(L"%s\n",CkHttpW_lastErrorText(http));
        CkHttpRequestW_Dispose(req);
        CkHttpW_Dispose(http);
        CkHttpResponseW_Dispose(resp);
        return;
    }

    wprintf(L"HTTP response status: %d\n",CkHttpResponseW_getStatusCode(resp));

    // 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:
    htmlStr = CkHttpResponseW_bodyStr(resp);
    wprintf(L"Received:\n");
    wprintf(L"%s\n",htmlStr);


    CkHttpRequestW_Dispose(req);
    CkHttpW_Dispose(http);
    CkHttpResponseW_Dispose(resp);

    }