In a VB.net application, retrieving variables from a database, if the value was null, it would cause the error, “Conversion from type ‘DBNull’ to type ‘String’ is not valid”.  A work-around to stop this error was to create a function that would evaluate the imported database variable for a null value as an object then convert it to a string for use without error in your code.

Here is the VB.net code:


Function checkNull(Byval variable as object) as String
If IsDBNull(varialbe) Then
Return("")
Else
Return (variable)
End If
End Function