This question already has answers here: 开发者_高级运维 Closed 11 years ago. Possible Duplicate: What's the difference between 'int?' and 'int' in C#?
I have a class (used by filehelpers) which gives me an error when I try to define a nullable string: public String开发者_StackOverflow社区? ItemNum;
I have a method that is defined like such: public bool IsValid(string propertyName, object propertyValue)
I\'m trying to compare two variables of type nullable(of boolean) in VB.NET 2010. One of the variables has a value False and the other is Nothing. Now I was expecting the following expression to evalu
I have a problem inserting NULL in Django. I mean i don\'t know how to do this. I have function, lets call it find_position, then i have field in model like position (IntegerField, null=True, blank=T
Is there a way to optimize following query? It returns the right records but takes more than a minute 开发者_如何转开发to execute.
I\'ve got a table with some nullable double fields. Working with LinqToSQL trying to use the field directly I get
I have a statement like DateTime ? dt = (string1 == string2) ? null; (DateTime)(txtbox.Text); which I cannot compile. Reason is : null cannot be assigned to DateTime.
what does the question mark mean at the end of the variable? TimeSpan? begin = // bla bla bla The c开发者_如何学运维oding language is c#This is Nullable type. It means that value of begin can be nu
I quote the following paragraphs from the book: The C# Programming Language Fourth Edition C# supports single- and
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