Goal
You are creating a c# or vb.net program and when
you try to compile you get an "Extension method must be defined in a non-generic
static class". This happens to you, for instance if you are creating a windows
service in c# and you just keep adding voids and functions to you main class in
the namespace of the project. It can be
any type of project I don’t mean to pick on windows services.
Environment
Windows 7 64 bit and Visual Studio 2010.
Issue
In my case I added many public static functions to my main class which is of course not static. Static voids or functions need to belong to a static class.
Resolution
Add a class to your project. Make the class you create a public static class. Cut and paste your static voids and functions in. Reference your voids and subs using the syntax: ClassName.FuntionorVoid();
For example in my project I have a bunch of c# functions that do vb.net functions like right. I created a public static class called DataChecks. The syntax to call it from my main class is below:
fields[7] = "0." + DataChecks.Right("00"
+ fields[7].ToString().Trim(), 2);
Because it is public and static you can just reference it anywhere in the namespace using classname.voidorfunction. If it were not static public you would need to:
ClassName myname = new ClassName();
Myname.voidoffunction();
Either way, the moral of the lesson is not to mix statics and non-statics.
Conclusion
If you are like me, it is easy to want to get a project done quickly and forget some basic tenets, like you can’t put statics in a regular class. This will cost you debug time. You should break out your project in meaningful classes anyway, its just good practice.
