[RESOLVED] Data Reader Null problem

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Hi,
looking at the code below you can see Im just filling a data table through a data reader. But everytime I try read a value that is null I get a SQLNullValueException this method or action cannot be called on NullValues.

VB Code:

Do While objDatabase.SqlRdrCustomers.Read
                dr = ddsRecommends.tblRecommends.NewRow()
                dr("PK_RecommendID") = objDatabase.SqlRdrCustomers.GetValue(0)
                dr("FK_SaleNo") = objDatabase.SqlRdrCustomers.GetValue(1)
                dr("InsertDate") = objDatabase.SqlRdrCustomers.GetDateTime(2)
                dr("Status") = objDatabase.SqlRdrCustomers.GetValue(3)
                dr("DateOfSale") = objDatabase.SqlRdrCustomers.GetDateTime(4)
  [U]              dr("DateLastLetterSent") = objDatabase.SqlRdrCustomers.GetDateTime(5)[/U]
                dr("LettersSentCount") = objDatabase.SqlRdrCustomers.GetValue(6)
                dr("CustName") = objDatabase.SqlRdrCustomers.GetString(7)
                ddsRecommends.tblRecommends.Rows.Add(dr)
                objMainform.ProgressBar1.PerformStep()
            Loop

Oct 21st, 2005, 08:36 AM
kleinma

Re: Data Reader Null problem

well it looks to me as though the value of objDatabase.SqlRdrCustomers.GetDateTime(5) is null... if that is the case, you need to add some extra handling code to handle situations where the code encounters a null value
Oct 21st, 2005, 08:40 AM
FishGuy

Re: Data Reader Null problem
I tried this but then I get the error
"Is requires operands that have reference types but this operand has the type 'Date'"
VB Code:
```
If Not [U]objDatabase.SqlRdrCustomers.GetDateTime(5)[/U] Is DBNull.Value Then dr("DateOfSale") = objDatabase.SqlRdrCustomers.GetDateTime(4)
```
Oct 21st, 2005, 08:42 AM
kleinma

Re: Data Reader Null problem
try
VB Code:
```
If Not objDatabase.SqlRdrCustomers.GetDateTime(4) [b]=[/b] DBNull.Value then
```
although it is early and I have not had my coffee yet ;)

Re: Data Reader Null problem

Instead of

VB Code:

If Not objDatabase.SqlRdrCustomers.[COLOR=DarkRed]GetDateTime(4)[/COLOR] Is DBNull.Value Then dr("DateOfSale") = objDatabase.SqlRdrCustomers.GetDateTime(4)

Try

VB Code:

If Not objDatabase.[COLOR=DarkRed]SqlRdrCustomers(4)[/COLOR] Is DBNull.Value Then dr("DateOfSale") = objDatabase.SqlRdrCustomers.GetDateTime(4)

Re: Data Reader Null problem

Instead use

VB Code:

If Not objDatabase.SqlRdrCustomers(4) Is DBNull.Value Then dr("DateOfSale") = objDatabase.SqlRdrCustomers.GetDateTime(4)

Oct 21st, 2005, 08:44 AM
FishGuy

Re: Data Reader Null problem
"Operator = is not defined for types 'Date' and 'System.DBNull'"
VB Code:
```
If Not [U]objDatabase.SqlRdrCustomers.GetDateTime(4) = DBNull[/U].Value then
```
Oct 21st, 2005, 08:53 AM
kleinma

Re: [RESOLVED] Data Reader Null problem

see i knew i needed my coffee..

so fish is it resolved as your topic says? or are you still having problems?