Categories: C#.Net

Personal note: Passing the Torch on the Open-Source Project QRCoder

Posted by Raffael on Posted in C#.Net, Personal stuff, Programming Tagged ,

Anyone who has searched this blog in recent years for solutions to generate QR codes in .NET will inevitably have come across my project, QRCoder. I launched the library in October 2013, not primarily because I lacked other tools at the time, but as a personal programming challenge: My goal was to implement the official DIN/ISO standard for QR codes natively in C# from scratch myself. To understand the algorithms, to learn something new.
Over the years, this experiment has grown into a very successful open-source project that has now been downloaded millions of times via NuGet and is used in numerous commercial and private projects worldwide.
After 12 years, I decided in September 2025 to hand over the active maintenance and administrative management of the project. In this brief post, I would like to explain the background behind this decision and introduce the new maintainer.
The Reasons for the Transition
Maintaining […]

Check Paypal account balance and transactions via C# API

Posted by Raffael on Posted in C#.Net, Programming Tagged , , , ,

How to use Paypal-API in CsharpAfter we had a look at how to sent push notifications via C# recently, there are plans for the next C# article today. This time it’s about how to read account balance, sales and transactions and other things of a Paypal account.
First some basic information. Although Paypal is an “online account”, in many ways it differs from an online (giro) account of a “classic” bank. For example, Paypal does not support the Homebanking Computer Interface (HBCI) to retrieve account information or send payments. Instead, Paypal offers different APIs (REST, SOAP, + SDKs, …), which differ not only in structure and technology, but especially in the range of functions. For our purposes we will use the so-called “NVP / SOAP API” and connect to it […]

How to send push notifications in C#

Posted by Raffael on Posted in Android, C#.Net, News & Apps, Programming, Test

Push-notifications-in C-SharpIn today’s article, we’ll look at how to push notifications out of C# onto smartphones or other devices. It does not matter if it is an Android or an Apple / iOS device. But when do you need such functionality?
For example, I run a few niche sites (affiliate websites) with which I earn monthly through affiliate programs. However, the revenue reports have to be picked up proactively in almost all affiliate programs. So I wrote a small C# client, which regularly downloads the reports and sends me a push notification for new sales. That’s just one of many uses and I’m sure you’ll think of a few more. But now back to the topic.
Selection of push platform
For a quick and easy integration of the push functionality […]

How to generate Swiss QR Code in C# and VBA

Posted by Raffael on Posted in C#.Net, Programming, Test, VBA Tagged , , ,

Swiss QR Code in C-Sharp and VBAToday, we are looking into the field of business computer science. Since end of April, SIX has released the specification for the new Swiss QR Code according to ISO 20022. The Swiss QR Code is an integral part of the new Swiss deposit slip, the so-called QR invoice, which shall be implemented by all companies by mid-2018 at the latest. The Swiss QR code is placed in the so-called “number part with QR code” of the QR invoice.
In the following, we will discuss how the Swiss QR code can be generated using C # or VBA. To do this, we use the free QRCoder library, which I developed almost 4 years ago and to which recently added the Swiss QR Code. One more […]

.NET Core – gdiplus.dll not found in Linux

Posted by Raffael on Posted in C#.Net, Kubuntu, Linux, Linux Mint, Programming, Test, Ubuntu Server

A few days ago there was an issue raised in my QrCoder project. It was reported that the code would not run under Linux, as the following error message would occur:

Unhandled Exception: System.TypeInitializationException: The type initializer for ‘System.Drawing.KnownColors’ threw an exception.
—> System.TypeInitializationException: The type initializer for ‘System.Drawing.GDIPlus’ threw an exception.
—> System.DllNotFoundException: Unable to load DLL ‘gdiplus.dll’: The specified module could not be found.
(Exception from HRESULT: 0x8007007E)
at System.Drawing.GDIPlus.GdiplusStartup(UInt64& token, GdiplusStartupInput& input,
[…]

However the error message had its origin not in my QrCoder, but in the interplay of the .NET core framework with the GDI Plus library. The .NET Core Framework tries to access “gdiplus.dll” when accessing “System.Drawing.GDIPlus”, which is simply not available on Linux.
First solution approach
First, ensure that GDI+ is installed at all. This can be done with the following shell command:

sudo apt-get install libgdiplus

If libgdiplus is installed, however, another important step is missing …
Link libgdiplus for .NET Core
Because the […]