Vb.net db null

Equals method. However, some languages and database objects supply methods that make it easier to determine whether the value of a database field is DBNull. IsDBNull method. Do not confuse the notion of null in an object-oriented programming language with a DBNull object. In an object-oriented programming language, null means the absence of a reference to an object.

DBNull represents an uninitialized variant or nonexistent database column. Represents the sole instance of the DBNull class. Gets the Type of the current instance. Creates a shallow copy of the current Object. Returns an empty string Empty. Returns an empty string using the specified IFormatProvider. This conversion is not supported. Attempting to make this conversion throws an InvalidCastException. Converts the current DBNull object to the specified type. Skip to main content.

This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Connect and share knowledge within a single location that is structured and easy to search. However, some of the fields in myDataTable cotain dbNull data.

So, the following VB. So, how do i get the above code to work when the fields may contain dbNull without having to check each time if the data is dbNull as in this question? My NotNull function has gone through a couple of overhauls over the years. Prior to Generics, I simply specified everything as an Object.

But I much prefer the Generic version. You can also use the Convert. ToString and Convert. ToInteger methods to convert items with DB null effectivly. A variation on Steve Wortham's code , to be used nominally with nullable types:.

Microsoft came up with DBNull in. NET 1. However, it's a pain in the behind to use because you can't create a strongly-typed variable to store a genuine value or null.

Microsoft sort of solved that problem in. NET 2. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 13 years, 2 months ago. Active 2 months ago.

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Privacy policy. Thank you. Microsoft makes no warranties, express or implied, with respect to the information provided here. Represents the sole instance of the DBNull class. The following example calls the DBNull. Equals method to determine whether a database field in a contacts database has a valid value.