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C# Learning: using nullable types


Let’s say your program needs to work with a date and time value. Normally you’d use a
DateTime variable. But what if that variable doesn’t always have a value? That’s where
nullable types comes in really handy. All you need to do is add a question mark (?) to the end
of any value type, and it becomes a nullable type that you can set to null.


bool? myNulableInt = null;
DateTime? myNullableDate = null;

You will find out that the question mark T? is an alias for Nullable<T>.

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