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Unicode C++

QR Code Generator via api.qrserver.com REST API

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Demonstrates how to generate a QR code using the api.qrserver.com REST API service.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkHttpW.h>
#include <CkJsonObjectW.h>
#include <CkHttpResponseW.h>
#include <CkBinDataW.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkHttpW http;

    // Send the following GET request to get a binary response.
    // The body of the binary response contains the image data for the QR code.
    // https://api.qrserver.com/v1/create-qr-code/?data=[URL-encoded-text]&size=[pixels]x[pixels]

    CkJsonObjectW queryParams;
    queryParams.UpdateString(L"data",L"Hello World");
    queryParams.UpdateString(L"size",L"100x100");

    // Get a PNG file..
    // Possible formats are:
    // png
    // gif
    // jpeg
    // jpg
    // svg
    // eps
    // Case matters.  Use lowercase.
    queryParams.UpdateString(L"format",L"png");

    // Send the GET request to an endpoint.
    // Chilkat will add the url-encoded query params passed in the JSON.
    CkHttpResponseW resp;
    success = http.HttpParams(L"GET",L"https://api.qrserver.com/v1/create-qr-code/",queryParams,resp);
    if (success == false) {
        wprintf(L"%s\n",http.lastErrorText());
        return;
    }

    // Did it succeed?
    if (resp.get_StatusCode() != 200) {
        // The response body, if anything, would not be the image data, but would likely be the error text (or HTML, or whatever...)
        wprintf(L"%s\n",resp.bodyStr());
        wprintf(L"Response status = %d\n",resp.get_StatusCode());
        wprintf(L"Failed.\n");
        return;
    }

    // Success if we get here..
    // Save the binary body as the PNG file, or you can get the bytes of the PNG..
    success = resp.SaveBodyBinary(L"c:/temp/qa_output/qr_code.png");

    // Or get the bytes:
    CkBinDataW bd;
    resp.GetBodyBd(bd);
    // Use the bytes in bd...
    // See the online reference documentation for the function to access the bytes directly.

    wprintf(L"Success.\n");
    }