Code inspection: Type pattern and casts can be merged

This inspection reports switch cases that already check a value's type, but then repeat casts of the same switched expression inside the case body or guard. Using a pattern variable in the case label makes the code shorter and clearer, because the typed value is introduced once and reused everywhere in that case.

Example

                switch (obj)
                {
                    case int x when ((int)obj) > 0:
                        Console.WriteLine((int)obj);
                        break;
                }
            

                switch (obj)
                {
                    case int x when x > 0:
                        Console.WriteLine(x);
                        break;
                }
            

Quick-fix

Use the pattern variable instead of repeating the cast.

01 April 2026