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.NET Core 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 .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();

// 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]

Chilkat.JsonObject queryParams = new Chilkat.JsonObject();
queryParams.UpdateString("data","Hello World");
queryParams.UpdateString("size","100x100");

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

// Send the GET request to an endpoint.
// Chilkat will add the url-encoded query params passed in the JSON.
Chilkat.HttpResponse resp = new Chilkat.HttpResponse();
success = http.HttpParams("GET","https://api.qrserver.com/v1/create-qr-code/",queryParams,resp);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

// Did it succeed?
if (resp.StatusCode != 200) {
    // The response body, if anything, would not be the image data, but would likely be the error text (or HTML, or whatever...)
    Debug.WriteLine(resp.BodyStr);
    Debug.WriteLine("Response status = " + Convert.ToString(resp.StatusCode));
    Debug.WriteLine("Failed.");
    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("c:/temp/qa_output/qr_code.png");

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

Debug.WriteLine("Success.");