Introduction
Operator is introduced with
Nullable datatype inclusion in .NET Framework operator
?? can also be referred in words like '
In case of null, pick value from another'.
Scenario
Suppose you're assigning a value to Nullable bool like:
bool? b = null;
At the time of checking value, it will give you an error like:
if(b)
{
}So it's always preferable to use ?? to prevent error like:
if(b ?? false)
{
}It defines that, in case b is null, pick the value false.
?? can also be used in multiple choice of value like:
bool ? a = null
bool ? b = null
bool ? c = true
a = b ?? c ?? false;
That will check b first if b is undefined or null, then it will move further to check for c if that also has null then it will set false to a.
