What is string interpolation in Dart?

Answer (1) A nullable type by adding a question mark (?) after the type name. For example, a variable _contacts? can contain a value, or it can be null. Answer (2) It is called “Null-aware operators”.

This is with null safety, the question mark means that this String? can possibly be null and flutter will allow you to assign null to it . String can never be null and you’ll get an error before compiling.29 Mar 2021

This is with null safety, the question mark means that this String? can possibly be null and flutter will allow you to assign null to it . String can never be null and you’ll get an error before compiling.29 Mar 2021