does not contain a static 'Main' method WPF

Question

I had deleted the App.xaml file and added new class named App.cs as the entry point. The buildAction property is compile.

 

class App : Application

{

[STAThread()]

static void main()

{

}

}

But when i compile an error had shown: d:\Projects\....\obj\x86\Debug\Test.exe does not contain a static 'Main' method suitable for an entry point.
How to solve this?