Invoke static method in static class C# ASP.NET Web Forms

Question

I've placed a static class TestClass in the App_Code folder. The class contains a static method TestMethod. From Default.aspx.cs via Button_Click method, I'm trying to invoke TestMethod. - test = TestClass.TestMethod(). This gives error: 'TestClass' is inaccessible due to its protection level.

It feels like the static class and the _Default class should be placed into a common namespace, but this would "exclude" the Default.aspx controls references.

What am I doing wrong?

Answer 1

You need to declare TestClass as public:

public static class TestClass
{
    public static SomeType TestMethod()
    {
    }
}

The default visibility is internal for types and private for members of a type definition. The App_Code folder gets compiled into its own assembly, different from the assembly that is created when compiling the code behinds. internal types cannot be shared between assemblies (that's not 100% true but true in this case), hence why you are having this problem.

Answer 2

Try to make it public static.

public class TestClass{
   public static TestMethod(){}

}

Answer 3

Make sure TestClass is public:

public class TestClass
{
}

The default when adding a class to Visual Studio is to omit the "public".

Answer 4

确保方法原型上至少具有“内部”作用域。

Answer 5

Just because your class is static doesn't mean that it is accessible to all code/assemblies. Make sure that your static class has an access modifier (ie public) that is accessible by your web form.