FirstOrDefault returns NullReferenceException if no match is found

Question

Here is my code:

string displayName = Dictionary.FirstOrDefault(x => x.Value.ID == long.Parse(options.ID)).Value.DisplayName;

The code works

Answer 1

Simply use the question mark trick for null checks:

string displayName = Dictionary.FirstOrDefault(x => x.Value.ID == long.Parse(options.ID))?.Value.DisplayName ?? "DEFINE A DEFAULT DISPLAY NAME HERE";