What are nullable types in C#?

What are nullable types in C#?

Nullable types in C# allow you to assign null to value types, which normally cannot be null. They are defined using a '?' after the type, like 'int?'. This is useful for database operations where a value might be absent.

Can you give me an example of how to use nullable types?

Sure! Here's a simple example:

int? myNullableInt = null;
if (myNullableInt.HasValue)
{
    Console.WriteLine(myNullableInt.Value);
}
else
{
    Console.WriteLine("myNullableInt is null");
}

What happens if I try to access the value of a null nullable type?

If you try to access the value of a null nullable type without checking if it has a value, you'll get an InvalidOperationException. Always check with 'HasValue' or use the null-coalescing operator.

Are there any performance implications of using nullable types?

Nullable types do have a slight overhead compared to regular value types due to the additional storage for the null state, but in most cases, this is negligible.