Cast from type 'DBNull' to type 'String' is not valid.

On the viewproduct page if any of the db fields referenced in the SP are empty you get the above error, the error originates in the productsDB.vb file as follows

myProductDetails.ModelNumber = CStr(parameterModelNumber.Value)
myProductDetails.ModelName = CStr(parameterModelName.Value)
myProductDetails.ProductImage = CStr(parameterProductImage.Value).Trim()
myProductDetails.UnitCost = CType(parameterUnitCost.Value, Decimal)
myProductDetails.Description = CStr(parameterDescription.Value).Trim()

OK I can make the fields accept no nulls but If I need to add another field to the products table(which I do) that may be empty for some records I am going to get this error
Has anyone else found this problem or a possible workaround
Thanks in advance
2/12/2004 12:26:32 AM 1165 articles. 0 followers. Follow

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If Not (paramatername.value) Is Nothing Then

' assign to variable or bind to an object.
End If
Depending on how you are doing this, you may compare use <> , "" whatever is appropriate. This should be enough to get you started.
Chris Paterra

2/13/2004 12:38:01 PM

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