C# - Basic question: What is '?' ?

Posted by Amokrane on Stack Overflow See other posts from Stack Overflow or by Amokrane
Published on 2010-04-23T14:34:16Z Indexed on 2010/04/23 14:53 UTC
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c#

Hi,

I'm wondering what ? means in C# ?
I'm seeing things like: DateTime? or int?. I suppose this is C# specific to C# 4.0?
I can't look for it in Google because I don't know the name of this thing.
The problem is I'm using DateTime and I have a lot of cast errors (from DateTime to DateTime?).

Thank you

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C# - Basic question: What is '?' ? - Developer IT

C# - Basic question: What is '?' ?

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