What is nullable type

Question

Hi, What is nullable type in c sharp. Thanks.

Vulpes · Answer

An important point to note about nullable types (which are always value types) is that the 'null' they use is not the same as the 'null' used with reference types. For example this line: object obj = null; means that the object variable, obj, doesn't currently refer to an object. So 'null' represents the null reference which is the memory address 0x0000 on a 32-bit system. In contrast, this line: int? i = null; means that the Nullable variable, i, doesn't currently have a value i.e. its HasValue property is false. So 'null' is just syntactic sugar for this state of affairs and is nothing to do with memory addresses.

Prabhu Raja · Answer

Hi, Nullable types Placed, where you want to be able to have a primitive type with a null (or unknown) value. For More Reference: Nullable Types in C#

Tulasi · Answer

Hi Alok Pandey, Nullable in .Net 2.0, helps to determine whether variable has been assigned a value or not,lets take a small example int? a=null; //means this value might be null if(a.HasValue) a.Value.toString() //a.HasValue return true if it contains value else return "null value"; int b=null ;//error Example: Quiz application having option yes/no, but it should displayed "Not Attempted" when user does not make any choice. chk this url : http://www.codeproject.com/KB/cs/c__20_nullable_types.aspx If this helps you, then mark as "Correct Answer" Thank You

Rakesh Jha · Answer

you can refer the article from msdn, click here

What is nullable type

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