Code cleanup refactorings

Visual Studio provides several refactorings for cleaning up and improving code quality. You can access these refactorings through the Quick Actions and Refactorings menu (Ctrl+.).

Add null checks for all parameters

Applies to: C#

This refactoring creates and adds if statements that check nullity of all the nullable, non-checked parameters in a method, making the program more robust.

1. Place your cursor on any parameter within the method.

2. Press Ctrl+. to trigger the Quick Actions and Refactorings menu.

   

3. Select the option to Add null checks for all parameters.

   

Remove unreachable code

Applies to: C#, Visual Basic

This refactoring removes code that will never be executed because there's no path to the code snippet, improving readability and maintainability.

1. Place your cursor anywhere in the faded out code that is unreachable:

1. Next, do one of the following:

   • Keyboard
     • Press Ctrl+. to trigger the Quick Actions and Refactorings menu and select Remove unreachable code from the Preview window popup.
   • Mouse
     • Right-click the code, select the Quick Actions and Refactorings menu and select Remove unreachable code from the Preview window popup.

2. When you're happy with the change, press Enter or click the fix in the menu and the changes will be committed.

Example:

// Before
private void Method()
{
    throw new Exception(nameof(Method));
    Console.WriteLine($"Exception for method {nameof(Method)}");
}

// After
private void Method()
{
    throw new Exception(nameof(Method));
}

Remove unused references

Applies to: C#, Visual Basic

For SDK style projects only, this refactoring removes unused project references and NuGet packages, helping save space and reduce startup time.

1. Verify that the option is enabled.

   Select Tools > Options > Text Editor > C# > Advanced, and enable Show "Removed Unused References" command in Solution Explorer.

2. In Solution Explorer, right click on a project name or the Dependencies node.

3. Select Remove Unused References.

   

4. The Remove Unused References dialog opens, displaying references that have no usage in source code. Unused references are pre-selected for removal with an option to preserve references by selecting Keep from the Action drop down.

   

5. Click Apply to remove selected references.

Unused value assignments, variables, and parameters

Applies to: C#, Visual Basic

This feature fades out unused parameters and generates a warning for unused expression values. The compiler also performs a flow analysis to find any unused value assignments. Unused value assignments fade out and a light bulb appears with a Quick Action to remove the redundant assignment. Unused variables with unknown values show a Quick Action suggestion to use discards instead.

Sort usings

Applies to: C#, Visual Basic

This refactoring sorts using directives at the top of your file alphabetically, making it easier to find a specific using directive.

1. Select Edit from the menu bar.

2. Select Intellisense > Sort Usings.

   

3. You can also configure different settings for using directives in Tools > Options > Text Editor > C# > Advanced.

   

Related content

• Refactoring
• Preview Changes