Hybridzz Hybridzz - 2 months ago 30
Vb.net Question

exception while sorting data grid column "Object must be of type Double." after changing the value

I've a data grid

gridDetails
with columns
discount
and
total
filled from the database

Total
is readonly while
discount
is not. When the value of discount is changed, The total is recalculated as

gridDetails.Item(1, e.RowIndex).Value -= (Val(gridDetails.Item(2, e.RowIndex).Value))


after changing the value the column cant be sorted. it generates an exception

System.ArgumentException was unhandled
Message="Object must be of type Double."
Source="mscorlib"
StackTrace:
at System.Double.CompareTo(Object value)
at System.Collections.Comparer.Compare(Object a, Object b)
at System.Windows.Forms.DataGridViewRowCollection.RowComparer.CompareObjects(Object value1, Object value2, Int32 rowIndex1, Int32 rowIndex2)
at System.Windows.Forms.DataGridViewRowCollection.RowArrayList.Pivot(Int32 left, Int32 center, Int32 right)
at System.Windows.Forms.DataGridViewRowCollection.RowArrayList.CustomQuickSort(Int32 left, Int32 right)
at System.Windows.Forms.DataGridViewRowCollection.RowArrayList.CustomSort(RowComparer rowComparer)
at System.Windows.Forms.DataGridViewRowCollection.Sort(IComparer customComparer, Boolean ascending)
at System.Windows.Forms.DataGridView.SortInternal(IComparer comparer, DataGridViewColumn dataGridViewColumn, ListSortDirection direction)
at System.Windows.Forms.DataGridView.Sort(DataGridViewColumn dataGridViewColumn, ListSortDirection direction)
at System.Windows.Forms.DataGridView.OnColumnHeaderMouseClick(DataGridViewCellMouseEventArgs e)
at System.Windows.Forms.DataGridView.OnMouseClick(MouseEventArgs e)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.DataGridView.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(ApplicationContext context)
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun()
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel()
at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(String[] commandLine)
at cableguy.My.MyApplication.Main(String[] Args) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 81
at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException:


i've converted the result to double using Cdbl, DirectCast etc.. no hope
like
gridDetails.Item(1, e.RowIndex).Value = Cdbl(gridDetails.Item(1, e.RowIndex).Value-Val(gridDetails.Item(2, e.RowIndex).Value))


any idea??

Answer

what @WozzeC explained is the reason... am adding wht i've done to make it alright.. Before adding to grid i've converted the values to Double. Now its okei.. :) :happy:

read the data to a datareader and

 While data.Read = True
  Dim total_amount As Double = data("discount")
  Dim discount_amount As Double = data("total")
  gridDetails.Rows.Add(total_amount ,discount_amount)
 End While