nullable
Explanation of int? vs int [duplicate]
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#?[详细]
2023-03-13 22:09 分类:问答Class in c# (with filehelpers) - nullable strings giving an error when other nullable types aren't
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;[详细]
2023-03-13 13:09 分类:问答Detecting nullable types in C#
I have a method that is defined like such: public bool IsValid(string propertyName, object propertyValue)[详细]
2023-03-12 07:00 分类:问答comparing nullable(of boolean)
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[详细]
2023-03-12 00:13 分类:问答How to insert NULL in database using Django
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[详细]
2023-03-11 07:04 分类:问答Optimize query with NULLable column in Oracle
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.[详细]
2023-03-10 17:41 分类:问答How to correctly deal with System.Nullable<T> fields of LinqToSql classes?
I\'ve got a table with some nullable double fields. Working with LinqToSQL trying to use the field directly I get[详细]
2023-03-10 02:40 分类:问答Assigning null/Nullable to DateTime in Ternary Operation
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.[详细]
2023-03-09 20:16 分类:问答what does "timespan?" mean in c#?
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[详细]
2023-03-08 21:25 分类:问答Can array and nullable types be used before they are declared?
I quote the following paragraphs from the book: The C# Programming Language Fourth Edition C# supports single- and[详细]
2023-03-08 09:56 分类:问答