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? (question mark) after a type name in C#?

+3 votes
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What does ? (question mark) after a type name mean in C#?

posted Mar 25, 2014 by Muskan

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1 Answer

+1 vote
 
Best answer

This is a short hand for System.Nullable
The question mark states that it is a nullable type.
this syntax will allows you to store a null value for value types (which would otherwise not support null values.

Example:
private char? getLetter() {
if(something) {
return 'a';
else
return null;
}

char? letter = getLetter();
if(letter.HasValue) {
//do something with it
Debug.WriteLine(letter.Value);
}
else
//it's null!

answer Mar 26, 2014 by Atul Mishra
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