AutoComplete.DataSource - Reset technique

[Sam Horton]

I have the following code which runs normally the first time it is invoked but fails on any subsequent call. (User is selecting a field name sans '_' in one combo box, a textbox with an autofill needs to be changed as a result...)

The ArrayList() is clean.... What did I miss?

'Invoked when a combo box specifying a valid column is changed to re-populate autocomplete lookup list
Private iTotalRowCount As Integer, iRowCount As Integer, m_LastItem As String, m_TempItem As String
Public Sub FillAutoCompleteListByColName(ByVal dv As DataView, ByVal sColName As String, ByRef AutoCtl As Syncfusion.Windows.Forms.Tools.AutoComplete)
Dim tmpArray As New ArrayList()
sColName = sColName.Replace(" ", "_")
dv.Sort = sColName
m_LastItem = String.Empty

iTotalRowCount = dv.Count
If iTotalRowCount > 0 Then
For iRowCount = 0 To iTotalRowCount - 1
If (dv(iRowCount).Item(sColName).ToString <> String.Empty) Then
m_TempItem = dv(iRowCount).Item(sColName).ToString
If m_TempItem <> m_LastItem Then
tmpArray.Add(m_TempItem)
m_LastItem = m_TempItem
End If
End If
Next
End If

Try
AutoCtl.DataSource = tmpArray
' Line 202 above
Catch E As Exception
'MsgBox(E.ToString)
Console.WriteLine(E.ToString)
End
End Try

'Runs fine first time, autocomplete works great... Second time (or any subsequent) I see...

Syncfusion.Windows.Forms.Tools.DataSourceException: There was a problem with the specified DataSource. Please check the InnerException for more details. ---> System.NullReferenceException: Object reference not set to an instance of an object.
at System.Data.DataTable.InsertRow(DataRow row, Int32 proposedID, Int32 pos)
at System.Data.DataTable.AddRow(DataRow row, Int32 proposedID)
at System.Data.DataRowCollection.Add(DataRow row)
at Syncfusion.Windows.Forms.Tools.AutoComplete.SetTableData()
--- End of inner exception stack trace ---
at Syncfusion.Windows.Forms.Tools.AutoComplete.SetTableData()
at Syncfusion.Windows.Forms.Tools.AutoComplete.set_DataSource(Object value)
at TargetTrak_Pro.QuickFilter.FillAutoCompleteListByColName(DataView dv, String sColName, AutoComplete& AutoCtl) in C:\Documents and Settings\Sam\My Documents\Visual Studio Projects\TargetTrak_Pro\QuickFilter.vb:line 202
The program '[3096] TargetTrak_Pro.exe' has exited with code 0 (0x0).

[Sam Horton]

> I have the following code which runs normally the first time it is invoked but fails on any subsequent call. (User is selecting a field name sans '_' in one combo box, a textbox with an autofill needs to be changed as a result...)
>
> The ArrayList() is clean.... What did I miss?
>
> 'Invoked when a combo box specifying a valid column is changed to re-populate autocomplete lookup list
> Private iTotalRowCount As Integer, iRowCount As Integer, m_LastItem As String, m_TempItem As String
> Public Sub FillAutoCompleteListByColName(ByVal dv As DataView, ByVal sColName As String, ByRef AutoCtl As Syncfusion.Windows.Forms.Tools.AutoComplete)
> Dim tmpArray As New ArrayList()
> sColName = sColName.Replace(" ", "_")
> dv.Sort = sColName
> m_LastItem = String.Empty
>
> iTotalRowCount = dv.Count
> If iTotalRowCount > 0 Then
> For iRowCount = 0 To iTotalRowCount - 1
> If (dv(iRowCount).Item(sColName).ToString <> String.Empty) Then
> m_TempItem = dv(iRowCount).Item(sColName).ToString
> If m_TempItem <> m_LastItem Then
> tmpArray.Add(m_TempItem)
> m_LastItem = m_TempItem
> End If
> End If
> Next
> End If
>
> Try
> AutoCtl.DataSource = tmpArray
> ' Line 202 above
> Catch E As Exception
> 'MsgBox(E.ToString)
> Console.WriteLine(E.ToString)
> End
> End Try
>
> 'Runs fine first time, autocomplete works great... Second time (or any subsequent) I see...
>
> Syncfusion.Windows.Forms.Tools.DataSourceException: There was a problem with the specified DataSource. Please check the InnerException for more details. ---> System.NullReferenceException: Object reference not set to an instance of an object.
> at System.Data.DataTable.InsertRow(DataRow row, Int32 proposedID, Int32 pos)
> at System.Data.DataTable.AddRow(DataRow row, Int32 proposedID)
> at System.Data.DataRowCollection.Add(DataRow row)
> at Syncfusion.Windows.Forms.Tools.AutoComplete.SetTableData()
> --- End of inner exception stack trace ---
> at Syncfusion.Windows.Forms.Tools.AutoComplete.SetTableData()
> at Syncfusion.Windows.Forms.Tools.AutoComplete.set_DataSource(Object value)
> at TargetTrak_Pro.QuickFilter.FillAutoCompleteListByColName(DataView dv, String sColName, AutoComplete& AutoCtl) in C:\Documents and Settings\Sam\My Documents\Visual Studio Projects\TargetTrak_Pro\QuickFilter.vb:line 202
> The program '[3096] TargetTrak_Pro.exe' has exited with code 0 (0x0).

--update--
I have this working in a slightly different form, but if you have any recc. for an improvement or overlooked best approach I would appreciate the advice.......

Private iTotalRowCount As Integer, iRowCount As Integer, m_LastItem As String, m_TempItem As String
Public Sub FillAutoCompleteListByColNameWithBind(ByVal dv As DataView, ByVal sColName As String, ByRef bindTxtBox As Windows.Forms.TextBox)
Dim tmpArray As New ArrayList()

sColName = sColName.Replace(" ", "_")
dv.Sort = sColName
m_LastItem = String.Empty

iTotalRowCount = dv.Count
If iTotalRowCount > 0 Then
For iRowCount = 0 To iTotalRowCount - 1
If (dv(iRowCount).Item(sColName).ToString.Trim <> String.Empty) Then
m_TempItem = dv(iRowCount).Item(sColName).ToString
If m_TempItem <> m_LastItem Then
tmpArray.Add(m_TempItem)
m_LastItem = m_TempItem
End If
End If
Next
End If

tmpArray.TrimToSize()

Try
Dim newAutoCtl As New Syncfusion.Windows.Forms.Tools.AutoComplete()
newAutoCtl.AutoSerialize = False
newAutoCtl.BorderType = Syncfusion.Windows.Forms.Tools.AutoCompleteBorderTypes.Sizable
newAutoCtl.CategoryName = sColName
newAutoCtl.DataSource = tmpArray
newAutoCtl.SetAutoComplete(bindTxtBox, Syncfusion.Windows.Forms.Tools.AutoCompleteModes.AutoSuggest)
Catch E As Exception
'MsgBox(E.ToString)
Console.WriteLine(E.ToString)
End
End Try

End Sub

[Davis Jebaraj]

Hi Sam,

I will see what can be done to prevent this problem and get back to you.

Thank you for your patience.

Regards,

Davis