‘Nullable reference types’ and ‘Non-nullable reference types’ to allow the compiler to perform ‘static flow analysis’ for purpose of null-safety.
class_name variable_name; //’class_name’ is non-nullable reference type class_name? variable_name; //’class_name?’ is nullable reference type
Benefit: The compiler can perform a static analysis to identify where there is a possibility of ‘null’ values and can show warnings; so we can avoid NullReference Exceptions at coding-time itself.
By default, all classes and interfaces are ‘non-nullable reference types’. To convert them as ‘nullable reference type’, suffix a question mark (?). Eg: class?
Null forgiving operator (!)
Suffix your expression (variable or property) with “!” operator to make that expression as “not null”, at compilation time.
Developer says to the C# compiler – that, a variable or property is “not null”. But at run time, if it is actually null, it leads to “NullReference Exception” as normal.
So use this operator only when you are sure that your expression (variable of property) is NOT null.
