To use base type where possible
  1. Position the caret at the name of a type.
  2. Choose ReSharper | Refactor | Use Base Type Where Possible. The Use Base Type Where Possible dialog box displays:
  3. Specify the following options:
    • In the list of base types of the selected type, select which one to use for replacement.
    • Select whether you want to Replace types in 'is' operator and/or Replace types in 'typeof' operator.
  4. Click Next. If no conflicts are found, selected categories of references are updated immediately. Otherwise, resolve conflicts.