October 13, 2008 12:51pm pdt

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	[x] Attachment Details

Why is 'If reader1.HasRows = False Then Stop' the Boolean Value doesn't get updated after Reader.Read

[x]

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8.5

Zones: Language Integrated Query - LINQ, .Net Editors & IDEs

Tags: VB.NET, .NET, Invalid Operations Exception was unhandled: No data exists for row/column

reader1.read sucessfully reads ea row created with the OLESelect Statement, in the Code Loop.

However, when the last reader1 row is returned/read, the reader1.HasRows BOOLEAN Value shows 'TRUE'. Then instead of STOP line of being executed, in the Code, the next line of code abends w the error msg: Invalid Operations Exception was unhandled: No data exists for row/column.

I have also tried to use the boolean reader1.NextResults = False, to detect an EOF/NO ROWS, however the circumstance occurs. boolean value says 'TRUE', when the next reader1 process/ethod will cause a program exception w same error.

My specific questions, is how can I determine/detect when the last row in reader1 has been reached in the code logic.

A side questions, is how can I specifically see what reader.read record values and what the row/record #/postion in the dataset is, using VB.NET IDE. Specifically, when I look at the 'locals' pane for information on reader1. I get all sorts of Field Properties???, such as DEPTH/FIELD COUNT/IsClosed/ITEM ect ect. But if I expand a specific Field, I can't find any specific useful detail? Such as how many records are in the reader buffer, which record in the buffer, is the active record? Or how to display the record/row information in the IMMEDIATE pane of the IDE. For instance '?reader1.read' to display current active row/record or ?reader1.count.

Any assistance, wil be sincerely appreciated. Thanks

Mike

         
           
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             ConTble.Open()
        ConTbleR1.Open()
        'Debug.Print(ConTble.State)
 
        Dim OLESelect As String = "SELECT [NISADDRBK#], ENAME, NMNTH1, TMNTH1, NMNTH2, TMNTH2 FROM TMECrdRecs"
 
        Dim OLECmndR1 As OleDb.OleDbCommand = ConTble.CreateCommand()
        OLECmndR1.CommandText = OLESelect
        Dim OLECmnd As OleDb.OleDbCommand = ConTble.CreateCommand()
        OLECmnd.CommandText = OLESelect
 
        Dim reader1 As OleDb.OleDbDataReader
        reader1 = OLECmndR1.ExecuteReader
        reader1.Read()
        strNISnum = reader1("NISADDRBK#").ToString
        strNISnameVal = reader1("ENAME").ToString
        strNISnumVal = strNISnum
 
        lstTMERecKeys.Add(strNISnum, strNISnameVal)
        lstTMERecVals.Add(strNISnameVal, strNISnum)
 
        While reader1.HasRows
 
            If strNISnumVal <> strNISnum Then
                lstTMERecKeys.Add(strRecKey, strRecVal)
                lstTMERecVals.Add(strRecVal, strRecKey)
                strNISnumVal = strNISnum
            Else
                Do While strNISnum = strNISnumVal And reader1.HasRows
 
                    If reader1.HasRows = False Then Stop
 
                    initRec = reader1("NISADDRBK#").ToString & " " & reader1("ENAME").ToString
                    strRecKey = reader1("NISADDRBK#").ToString
                    strRecVal = reader1("ENAME").ToString
                    strNISnum = reader1("NISADDRBK#").ToString
                    If reader1.HasRows Then reader1.Read()
                    If reader1.HasRows = False Then Stop
 
                Loop
            End If
        End While
           
         

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