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How do I check if an object is null in vb? I tried using IsDBNull but it

doesn't work at all. It gives me this error when I try statement like If Not

IsDBNull(theStock.WIPQty) Then:



Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the

current web request. Please review the stack trace for more information about

the error and where it originated in the code.



Exception Details: System.NullReferenceException: Object reference not set

to an instance of an object.


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IsDBNull is to check for NULL for values coming from a DB. Here it looks

like that "theStock" is Nothing (null in C#).



Patrice



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"wrytat" <wrytat@discussions.microsoft.com>a écrit dans le message de



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Oh~ Then how do I check that if it is null in VB?



"Patrice" wrote:

If (yourobject Is Nothing) Then



"wrytat" <wrytat@discussions.microsoft.com>wrote in message



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ROFLMOD!



Never mind. It's Nothing.



--

HTH,



Kevin Spencer

Microsoft MVP

.Net Developer

Sometimes you eat the elephant.

Sometimes the elephant eats you.



"wrytat" <wrytat@discussions.microsoft.com>wrote in message



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Ok Thanks. Actually what is the difference between null value and nothing?

Very complicated...



"MW de Jager" wrote:

NULL in a database means that the value is not "defined" (i.e. if the price

column for the product is NULL the price is not known, 0 would mean it is

free). This is called DBNull in .NET.



"Nothing" (null in C#) means that the object doesn't exist... (basically

objects are pointers, it means that this pointer is not yet defined).



Patrice



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"wrytat" <wrytat@discussions.microsoft.com>a écrit dans le message de



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The difference between null and Nothing is the language you're coding in.

"null" is C# for "Nothing" in VB, which is "nada" in Espanol. However,

Espanol is not a programming language. ;-)



--

HTH,



Kevin Spencer

Microsoft MVP

.Net Developer

Sometimes you eat the elephant.

Sometimes the elephant eats you.



"wrytat" <wrytat@discussions.microsoft.com>wrote in message



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