Nullable Types
Nullable types are variables that can be assigned with the value ‘null’. Allmost all value types can be declared as a nullable type. To declare a
value type as a nullable type, you have to add a questionmark after the type name.
For example:
char? a = null;
bool? b = null;
int? c = null;
double? d = null;
Nullable type has two read-only properties: HasValue and Value.
HasValue is a bool property. If the current value is ‘null’,
HasValue will return false, otherwise it will return true. The HasValue property can be used to test if a variable contains a value.
For Example :
int? test = 10;
if (test .HasValue)
{
Console.WriteLine(test .Value);
}
else
{
Console.WriteLine(“no value”);
}
How to convert Nullable Type to NON-Nullable Type
int? intValue1 = null;
int intValue2 = intValue1 ?? 10;