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c#custom-attributespostsharp

Generating a custom compile time warning


I'm using VS2008 and would like to create a compile time warning / error based on custom attributes on a property (if it is possible).

There are two cases which interest me currently:

[MyAttribute (typeof(MyClass)]

Where MyClass has to implement an interface. Currently I assert this in the constructor of the attribute, however this doesn't make it easy to track down, due to the nature of the stack trace:

public MyAttribute (Type MyClassType)
{
    System.Diagnostics.Debug.Assert(
        typeof(MyInterface).IsAssignableFrom(MyClassType),
        "Editor must implement interface: " + typeof(MyInterface).Name);
}

The second case which interests me is where I have a type defined in an attribute, if that type implements an interface, then a warning should be displayed if another attribute isn't present.

I.E. if (MyClass.Implements(SomeInterface) && !Exists(SomeAttibute)) { Generate Warning }

[MyAttribute(typeof(MyClass)] 
// Comment next line to generate warning
[Foo ("Bar")]

Thanks!


Solution

  • You can do that with PostSharp.

    I've once done it, and explained how to do it here