C# Error
CS1722 – Base class ‘{0}’ must come before any interfaces
Reason for the Error & Solution
Base class ‘class’ must come before any interfaces
When specifying a class to inherit from and interfaces to implement, the class name must be specified first.
Example
The following sample generates CS1722.
// CS1722.cs
// compile with: /target:library
public class A {}
interface I {}
public class MyClass : I, A {} // CS1722
public class MyClass2 : A, I {} // OK