JS1220: Expando methods cannot override base class methods

A method has both expando and override modifiers. This is not allowed since the expando method is associated with the current class, and override only applies to members associated with a class instance.

To correct this error

  • Remove either the expando or override modifier from the method declaration.

See Also

Concepts

Troubleshooting Your Scripts

JScript Modifiers

Other Resources

JScript Reference