Decompiling VB.Net assembly produces code with invalid member variable names; names starting with $STATIC$

Question

I am doing work for a client who has lost the source code for one of their VB.Net WinForms applications. The assembly they have is not obfuscated at all. I am trying to reco

Answer 1

Those are identifiers generated by the VB.NET compiler to implement the Static keyword. For example:

Class Example
    Public Sub test()
        Static lookhere As Integer = 42
    End Sub
End Class

generates this IL:

.field private specialname int32 $STATIC$test$2001$lookhere
.field private specialname class [Microsoft.VisualBasic]Microsoft.VisualBasic.CompilerServices.StaticLocalInitFlag $STATIC$test$2001$lookhere$Init

By using reserved letters in the field name, the compiler can be sure there will never be an accidental collision with another field. There's no direct equivalent to Static in the C# language. You can leave them as private fields in the class but you have to watch out for initialization. The purpose of the $Init flag and rather a lot of IL that ensures the variable is correctly initialized. You'll need to rename them by hand.