ReSharper 2016.1 Help

Making Fields Readonly

It is often reasonable to use the 'readonly' modifier for fields that are assigned in the declaration or in a constructor and only have read usages. By default, ReSharper suggests you making a field readonly if the above conditions are met. It highlights such fields and suggests the corresponding quick-fix or fix in scope:

Make field readonly quick-fix

If you do not want ReSharper to suggest you this, you can change the severity level of the code inspection that detects it (Field can be made readonly).

The reverse functionality is also available. If you decide to change a readonly field later in your code (which leads to compiler error), ReSharper detects the error and suggests fixing it by removing the 'readonly' keyword from the filed:

Make non-readonly fix

Another option to make fields readonly in a bulk mode is code cleanup. You can either run code cleanup with the default profile Default: Full Cleanup or run the cleanup with a custom profile solely targeted at your specific task as described below.

To add the 'readonly' keyword to fields that only have read access

  1. Open the Code Cleanup options: ReSharper | Options | Code Editing | Code Cleanup.
  2. Create a new profile as described in the Configuring Code Cleanup section. In the Selected profile settings section for the new profile tick the Make field read-only, if possible check box.
  3. Click Save to apply the modifications and let ReSharper choose where to save them, or save the modifications to a specific settings layer using the Save To drop-down list. For more information, see Managing and Sharing ReSharper Settings.
  4. Select the scope where you want to make fields readonly:
    • Set the caret anywhere in the file to make fields readonly to the file.
    • Select one or more items in the Solution Explorer to make fields readonly in the files under these nodes and their child items.
  5. Do one of the following:
    • Press Ctrl+Alt+F or choose ReSharper | Edit | Cleanup Code in the main menu .
    • Right-click anywhere in the text editor or right-click the selection and choose Cleanup Code in the context menu.
  6. In the Code Cleanup dialog box that opens, select the newly created profile in the Available Profiles area.
  7. Click Run. ReSharper will make fields readonly in the selected scope.

If you want to make fields readonly without opening the Code Cleanup dialog box, you can bind the created profile to the silent cleanup and run it simply by pressing Ctrl+Shift+Alt+F. You can also create a custom cleanup profile that would combine making fields readonly with other code style tasks.

This feature is supported in the following languages/technologies:

C# VB.NET C++ HTML ASPX Razor JavaScript TypeScript CSS XML XAML RESX Build Scripts Protobuf JSON

See Also

Last modified: 19 August 2016