.NET 6+
QuickOPC is a set of .NET components that simplify the task of integrating OPC into applications. It works in the "original" .NET Framework, and it also supports the new .NET 6+. This allows programs written with QuickOPC to run in different runtimes and on different operating systems; most importantly, not just on Microsoft Windows, but also on Linux and macOS, with the .NET 6+ runtime.
Have a look at the .NET Framework page for the description of the product features - what you find there, applies to .NET 6+ as well, wherever possible.
If you have previously developed with QuickOPC for .NET Framework and are now transitioning to .NET 6+, you may continue to use your existing code, as there are practically no coding differences between the two.There are, however, differences in other aspects, such as the supported functionality, tooling, installation, security, user interface, deployment, use of examples, etc.; more details.
When you target .NET 6+, OPC Unified Architecture and OPC XML-DA are directly supported.
You can use the "full" Visual Studio, .NET CLI Tools, JetBrains Rider, Visual Studio Code, or other tools to develop with QuickOPC for .NET 6+.
Simple QuickOPC Code Example in C#
The code below subscribes to changes of a monitored item value, and displays the value with each change. It runs in multiple .NET runtimes supporting .NET 6+, on Microsoft Windows or Linux:
// The callback is a lambda expression that displays the value
EasyUAClient.SharedInstance.SubscribeDataChange(
"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10853", 1000,
(_, args) => Console.WriteLine(args.AttributeData.Value));
Footnote & required disclosure: QuickOPC (including its Options) is a software development kit (SDK) for development of OPC clients. Installing QuickOPC or its Options does not change system settings.