datagridviewtextboxcell error on 350 characters

Rhyde Marsh

this i my first post, so i hope i am explaining it correctly, have a datagridview with a textboxcolumn. it is bind to a dataset my problem is when i update a record wiht more that 350 characters it give me a nullrefference error. the database is updated when i check the physical record but the application crash here is the function Private Sub m_maintenanceProcessor_WebsiteUpdated(ByVal sender As Object, ByVal e As Processors.EventArgs) Handles m_maintenanceProcessor.WebsiteUpdated Dim tempTable As MaintenanceDataSet.WebsitePageDownloadDataTable Try If e.Data.Contains("ModifiedRows") = False Then Exit Sub tempTable = CType(e.Data("ModifiedRows"), MaintenanceDataSet.WebsitePageDownloadDataTable) If tempTable.Rows.Count > 0 Then RemoveHandler maintenanceDataGridView.RowValidated, AddressOf maintenanceDataGridView_RowValidated Processor.Data.WebsitePageDownload.LoadingTable = True Processor.Data.WebsitePageDownload.Merge(tempTable, False) Processor.Data.WebsitePageDownload.LoadingTable = False Processor.Data.WebsitePageDownload.RejectChanges() AddHandler maintenanceDataGridView.RowValidated, AddressOf maintenanceDataGridView_RowValidated Processor.Data.WebsitePageDownload.Merge(tempTable) 'For Each row As DataRow In tempTable.Rows ' If row.RowError IsNot Nothing AndAlso row.RowError.Length > 0 Then ' MsgBox(row.RowError) ' End If ' ' MsgBox(row("URL").ToString) 'Next 'MsgBox(Processor.Data.WebsitePageDownload.Columns("defaultstatusid").MaxLength) Processor.Data.WebsitePageDownload.AcceptChanges() End If Catch ex As Exception MsgBox(ex.Message.ToString) End Try tempTable = Nothing Me.StatusMessage = String.Empty End Sub error gets thrown on acceptchanges

Lost User

Where does the error occur? Please edit your question and put <pre> tags around your code so it looks like:

Processor.Data.WebsitePageDownload.RejectChanges()
AddHandler maintenanceDataGridView.RowValidated, AddressOf maintenanceDataGridView_RowValidated

and indicate exactly which line the error occurs on.

Rhyde Marsh

Thanks for your response. The error occur on the acceptchanges line

Private Sub m_maintenanceProcessor_WebsiteUpdated(ByVal sender As Object, ByVal e As Processors.EventArgs) Handles m_maintenanceProcessor.WebsiteUpdated
Dim tempTable As MaintenanceDataSet.WebsitePageDownloadDataTable

      Try
          If e.Data.Contains("ModifiedRows") = False Then Exit Sub
          tempTable = CType(e.Data("ModifiedRows"), MaintenanceDataSet.WebsitePageDownloadDataTable)
          If tempTable.Rows.Count > 0 Then
              RemoveHandler maintenanceDataGridView.RowValidated, AddressOf maintenanceDataGridView\_RowValidated
              Processor.Data.WebsitePageDownload.LoadingTable = True
              Processor.Data.WebsitePageDownload.Merge(tempTable, False)
              Processor.Data.WebsitePageDownload.LoadingTable = False
              Processor.Data.WebsitePageDownload.RejectChanges()
              AddHandler maintenanceDataGridView.RowValidated, AddressOf maintenanceDataGridView\_RowValidated


              Processor.Data.WebsitePageDownload.Merge(tempTable)

              'For Each row As DataRow In tempTable.Rows
              '    If row.RowError IsNot Nothing AndAlso row.RowError.Length > 0 Then
              '        MsgBox(row.RowError)
              '    End If

              '    ' MsgBox(row("URL").ToString)

              'Next

              'MsgBox(Processor.Data.WebsitePageDownload.Columns("defaultstatusid").MaxLength)
              Processor.Data.WebsitePageDownload.AcceptChanges()
          End If
      Catch ex As Exception
          MsgBox(ex.Message.ToString)
      End Try
      tempTable = Nothing

      Me.StatusMessage = String.Empty

  End Sub

Lost User

You will need to use your debugger to find out which reference in that line is invalid.

Rhyde Marsh

what i know for a fact is the is a field that is set for 2000 characters but once this field goes over 350 the error gets triggered, other than that the application is fine

Lost User

Rhyde Marsh wrote:

what i know for a fact

But that is hardly relevant. Somewhere in your application something is being triggered which causes a null reference to be used. The only way to discover where that is and why, is to do some detailed debugging.

Lost User

2000 characters? In which encoding? UTF16?

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

ok i will get to that. juss that i have been looking and and dont see where

Rhyde Marsh

sorry for the late response but data field is set to nvarchar 2000 and the MaxInputLength set at 2000

Lost User

Rhyde Marsh wrote:

nvarchar

Good. Check the line

Processor.Data.WebsitePageDownload.AcceptChanges()

Set the cursor on the AcceptChanges method, hit F12. Set breakpoints there, and make sure that the method does not swallow the changes.

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

not sure what you mean swallow, but the data is updated but there seems to be a problem when it returns to the UI

Lost User

Rhyde Marsh wrote:

not sure what you mean swallow,

I'm expecting a try-catch in that method that hides the exception that is thrown.

Rhyde Marsh wrote:

the data is updated but there seems to be a problem when it returns to the UI

Is the data updated beyond the 350-char mark? How do you know there's a problem? Do you have an exception and a stack-trace?

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

yes it updates but then i get a nullrefference exception. so before the 350 mark it updates and refresh fine but anything after that i get the error

Lost User

Rhyde Marsh wrote:

nullrefference exception

I assumed that was fixed, based on your previous post. Can you post the entire stacktrace from the exception?

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

no my problem was not solved, but i it seem to be on bug on microsoft side in the control s at System.Windows.Forms.DataGridView.ComputeVisibleColumns() at System.Windows.Forms.DataGridView.LayoutScrollBars() at System.Windows.Forms.DataGridView.ComputeLayout() at System.Windows.Forms.DataGridView.PerformLayoutPrivate(Boolean useRowShortcut, Boolean computeVisibleRows, Boolean invalidInAdjustFillingColumns, Boolean repositionEditingControl) at System.Windows.Forms.DataGridView.ResetUIState(Boolean useRowShortcut, Boolean computeVisibleRows) at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged_PreNotification(CollectionChangeAction cca, Int32 rowIndex, Int32 rowCount, DataGridViewRow& dataGridViewRow, Boolean changeIsInsertion) at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged(CollectionChangeEventArgs e, Int32 rowIndex, Int32 rowCount, Boolean changeIsDeletion, Boolean changeIsInsertion, Boolean recreateNewRow, Point newCurrentCell) at System.Windows.Forms.DataGridViewRowCollection.ClearInternal(Boolean recreateNewRow) at System.Windows.Forms.DataGridView.RefreshRows(Boolean scrollIntoView) at System.Windows.Forms.DataGridView.DataGridViewDataConnection.ProcessListChanged(ListChangedEventArgs e) at System.Windows.Forms.DataGridView.DataGridViewDataConnection.currencyManager_ListChanged(Object sender, ListChangedEventArgs e) at System.Windows.Forms.CurrencyManager.OnListChanged(ListChangedEventArgs e) at System.Windows.Forms.CurrencyManager.List_ListChanged(Object sender, ListChangedEventArgs e) at System.Data.DataView.OnListChanged(ListChangedEventArgs e) at System.Data.Listeners`1.Notify[T1,T2,T3](T1 arg1, T2 arg2, T3 arg3, Action`4 action) at System.Data.Index.OnListChanged(ListChangedEventArgs e) at System.Data.DataTable.ResetInternalIndexes(DataColumn column) at System.Data.DataTable.Clear(Boolean clearAll) at MCAP.MaintenanceDataSetTableAdapters.WebsitePageDownloadTableAdapter.FillByWhereClause(WebsitePageDownloadDataTable dataTable, String whereClause) in C:\Users\mmarshall.MTMOBAY\Desktop\Mark\MCAP\DataSet\MaintenanceDataSet.Designer.vb:line 35940 at MCAP.UI.Processors.Maintenance.LoadFilteredWebsite(String filterCondition) in C:\Users\mmarshall.MTMOBAY\Desktop\Mark\MCAP\UIProcess\Maintenance.vb:line 6328 i found similar issue on microsoft site

Lost User

That could be tested easily by giving the columns a fixed width :)

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

yes, but cannot be limited because the length of the url entered is unknown

Lost User

This is not helping much, we're talking about different things. If you can fix the size of the column in the grid in where it is displayed to 100 pixels, then you can still enter long strings. It would prove whether or not the observed behaviour is caused by the internal resizing, or somewhere else. If fixing the width helps, then you'll need to look for other alternatives or find a fix. If fixing the width does not help, then the error is occurring somewhere else.

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^]

Rhyde Marsh

had to change the column to accomodate a popup wasnt getting anywhere with it