(MFC) HTTP Download to Stream

Demonstrates how to stream the response body directly to a stream, which in this case is to a file stream.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkRest.h>
#include <CkUrl.h>
#include <CkStream.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkRest rest;

    // The URL we want to download is: 
    // https://github.com/chilkatsoft/OAuth2-CSharp-Desktop/archive/master.zip
    CkUrl url;
    url.ParseUrl("https://github.com/chilkatsoft/OAuth2-CSharp-Desktop/archive/master.zip");

    // Connect to the web server
    bool bAutoReconnect = true;
    bool success = rest.Connect(url.host(),url.get_Port(),url.get_Ssl(),bAutoReconnect);
    if (success != true) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    success = rest.SendReqNoBody("GET",url.path());
    if (success != true) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Read the response header.
    int responseStatusCode = rest.ReadResponseHeader();
    if (responseStatusCode < 0) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    strOut.append("Response status code = ");
    strOut.appendInt(responseStatusCode);
    strOut.append("\r\n");

    // We expect a 200 response status if the file data is coming.
    // Otherwise, we'll get a string response body with an error message(or no response body).
    if (responseStatusCode == 200) {

        CkStream bodyStream;

        // The stream's sink will be a file.
        bodyStream.put_SinkFile("qa_output/OAuth2-CSharp-Desktop/archive/master.zip");

        // Read the response body to the stream.  Given that we've
        // set the stream's sink to a file, it will stream directly
        // to the file.
        success = rest.ReadRespBodyStream(bodyStream,true);
        if (success != true) {
            strOut.append(rest.lastErrorText());
            strOut.append("\r\n");
            SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
            return;
        }

        strOut.append("Successfully downloaded the file.");
        strOut.append("\r\n");

    }
    else {
        const char *errResponse = rest.readRespBodyString();
        if (rest.get_LastMethodSuccess() != true) {
            strOut.append(rest.lastErrorText());
            strOut.append("\r\n");
        }
        else {
            strOut.append(errResponse);
            strOut.append("\r\n");
        }

    }



    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }