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VB.NET IsNull?

Posted on 2003-12-01
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Last Modified: 2008-05-30
in vb6 there was IsNull()... is there a replacement in vb.net?

   - Marc
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Question by:MarcGraff
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appari earned 500 total points
ID: 9855244
there is no direct function as in VB 6.

but there are few otherways of checking for null. like check whether the variable is nothing or using dbNull. here is an example which i use in my .net projects, code is from http://www.freevbcode.com/ShowCode.Asp?ID=5810

    Enum enumObjectType
        StrType = 0
        IntType = 1
        DblType = 2
    End Enum

Public Function CheckDBNull(ByVal obj As Object, _
    Optional ByVal ObjectType As enumObjectType = enumObjectType.StrType) As Object
        Dim objReturn As Object
        objReturn = obj
        If ObjectType = enumObjectType.StrType And IsDBNull(obj) Then
            objReturn = ""
        ElseIf ObjectType = enumObjectType.IntType And IsDBNull(obj) Then
            objReturn = 0
        ElseIf ObjectType = enumObjectType.DblType And IsDBNull(obj) Then
            objReturn = 0.0
        End If
        Return objReturn
 End Function

you can change above function to suit your needs.
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by:MarcGraff
ID: 9855376
Wow! Works great! Thanks!

   - Marc
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