What are two question marks flutter?

The Dart language now supports sound null safety ! When you opt into null safety, types in your code are non-nullable by default, meaning that variables can’t contain null unless you say they can. With null safety, your runtime null-dereference errors turn into edit-time analysis errors.

String interpolation is the process of inserting variable values into placeholders in a string literal . To concatenate strings in Dart, we can utilize string interpolation. We use the ${} symbol to implement string interpolation in your code.

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

double question mark operator means “if null “.

double question mark operator means “if null “.

Null-aware operators are used in almost every programming language to check whether the given variable value is Null . The keyword for Null in the programming language Dart is null. Null means a variable which has no values assign ever and the variable is initialized with nothing like.