问题描述
有时当我对datagridview进行更改时 - 例如删除列，或重命名列标题，或者接受基础数据表上的更改，我得到了空引用异常。
堆栈跟踪在System.Windows.Forms.DataGridView.ComputeVisibleColumns结束并从System开始.Windows.Forms.NativeWindowCallback。
我想尽可能防止这种情况发生或以某种方式捕获它。
我尝试创建一个继承自datagridview的datagridview类，并使用a覆盖跟踪中的一些函数尝试catch捕获异常，但它仍然将其抛出_COMPlusException，或者如果没有地方可以捕获异常，那么它会抛出错误并导致应用程序崩溃。
我不知道该怎么做。
我确实看到这被报告为微软的一个错误但无法复制。我真的很感激有关如何处理这个的任何想法。
System.NullReferenceException：对象引用未设置为对象的实例。 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）
System.Windows.Forms.DataGridView.OnBandThicknessChanged的System.Windows.Forms.DataGridView.OnColumnWidthChanged（DataGridViewColumnEventArgs e）
（DataGridViewBand dataGridViewBand）
在System.Windows.Forms.DataGridView.AutoResizeColumnInternal（Int32 columnIndex，DataGridViewAutoSizeColumnCriteriaInternal autoSizeColumnCriteriaInternal，Boolean fixedHeight）
at System.Windows.Forms.DataGridView.AutoResizeAllVisibleColumnsInte rnal（DataGridViewAutoSizeColumnCriteriaInternal autoSizeColumnCriteriaFilter，Boolean fixedHeight）
System.Windows.Forms.DataGridView.OnAddedRow_PostNotification（Int32 rowIndex）
at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged_PostNotification（CollectionChangeAction cca，Int32 rowIndex，Int32 rowCount，DataGridViewRow dataGridViewRow ，布尔值changeIsDeletion，Boolean changeIsInsertion，Boolean recreateNewRow，Point newCurrentCell）
at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged（CollectionChangeEventArgs e，Int32 rowIndex，Int32 rowCount）
at System.Windows.Forms.DataGridViewRowCollection.AddInternal（ DataGridViewRow dataGridViewRow）
System.Windows.Forms.Forms.Forms.DataGridView.DataGridViewDataConnection.ProcessListChanged（ListChangedEventArgs e）
System.Windows.Forms.DataGridView的System.Windows.Forms.DataGridView.RefreshRows（Boolean scrollIntoView） .DataGridViewDataConnection.currencyManager _ListChanged（Object sender，ListChangedEventArgs e）
System.Windows.Forms.CurrencyManager.OnListChanged（ListChangedEventArgs e）
System.Windows.Forms.CurrencyManager.List_ListChanged（Object sender，ListChangedEventArgs e）
at System System.Data.Data.OnListChanged（ListChangedEventArgs e）
System.Data.DataView.UpdateIndex（Boolean force，Boolean fireEvent）
System.Data.Data.UpdateIndex（Boolean force）
System.Data .DataView.SetIndex2（String newSort，DataViewRowState newRowStates，DataExpression newRowFilter，Boolean fireEvent）
System.Data.DataView.SetIndex（String newSort，DataViewRowState newRowStates，DataExpression newRowFilter）
at System.Data.DataView.set_Sort（字符串值）
System.Data.DataView.System.ComponentModel.IBindingList.ApplySort（PropertyDescriptor属性，ListSortDirection方向）
System.Windows.Forms.DataGridView.DataGridViewDataConnection.Sort（DataGridViewColumn dataGridVie） wColumn，ListSortDirection方向）
在System.Windows.Forms.DataGridView.SortInternal（IComparer比较器，DataGridViewColumn dataGridViewColumn，ListSortDirection方向）
在System.Windows.Forms.DataGridView.Sort（DataGridViewColumn dataGridViewColumn，ListSortDirection方向）
System.Windows.Forms.DataGridView.OnColumnHeaderMouseClick（DataGridViewCellMouseEventArgs e）
在System.Windows.Forms.Forms.Control.WmMouseUp的System.Windows.Forms.DataGridView.OnMouseClick（MouseEventArgs e）
中。 m，MouseButtons按钮，Int32单击）
在System.Windows.Forms.Control.WndProc（Message& m）
System.Windows.Forms.DataGridView.WndProc（Message& m）
在System。 Windows.Forms.Control.ControlNativeWindow.OnMessage（Message& m）
System.Windows.Forms.Control.ControlNativeWindow.WndProc（Message& m）
System.Windows.Forms.NativeWindow.Callback（IntPtr hWnd ，Int32 msg，IntPtr wparam，IntPtr lparam）
Sometimes when I make a change to the datagridview - such as delete a column, or rename a column header, or acceptchanges on the underlying data table I get a Null Reference exception.
The stack trace ends at System.Windows.Forms.DataGridView.ComputeVisibleColumns and starts at System.Windows.Forms.NativeWindowCallback.
I want to prevent this from happening if possible or catch it somehow.
I tried creating a datagridview class that inherits from the datagridview and override some of the functions in the trace with a try catch to catch the exception but it still throws it up as _COMPlusException or if there is no place to catch the exception then it throws an error and crashes the application.
I don't know what to do about this.
I did see that this was reported as a bug to Microsoft but it could not be reproduced. I would really appreciate any ideas about how to deal with this.
System.NullReferenceException: Object reference not set to an instance of an object.
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.OnColumnWidthChanged(DataGridViewColumnEventArgs e)
at System.Windows.Forms.DataGridView.OnBandThicknessChanged(DataGridViewBand dataGridViewBand)
at System.Windows.Forms.DataGridView.AutoResizeColumnInternal(Int32 columnIndex, DataGridViewAutoSizeColumnCriteriaInternal autoSizeColumnCriteriaInternal, Boolean fixedHeight)
at System.Windows.Forms.DataGridView.AutoResizeAllVisibleColumnsInternal(DataGridViewAutoSizeColumnCriteriaInternal autoSizeColumnCriteriaFilter, Boolean fixedHeight)
at System.Windows.Forms.DataGridView.OnAddedRow_PostNotification(Int32 rowIndex)
at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged_PostNotification(CollectionChangeAction cca, Int32 rowIndex, Int32 rowCount, DataGridViewRow dataGridViewRow, Boolean changeIsDeletion, Boolean changeIsInsertion, Boolean recreateNewRow, Point newCurrentCell)
at System.Windows.Forms.DataGridViewRowCollection.OnCollectionChanged(CollectionChangeEventArgs e, Int32 rowIndex, Int32 rowCount)
at System.Windows.Forms.DataGridViewRowCollection.AddInternal(DataGridViewRow dataGridViewRow)
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.DataView.UpdateIndex(Boolean force, Boolean fireEvent)
at System.Data.DataView.UpdateIndex(Boolean force)
at System.Data.DataView.SetIndex2(String newSort, DataViewRowState newRowStates, DataExpression newRowFilter, Boolean fireEvent)
at System.Data.DataView.SetIndex(String newSort, DataViewRowState newRowStates, DataExpression newRowFilter)
at System.Data.DataView.set_Sort(String value)
at System.Data.DataView.System.ComponentModel.IBindingList.ApplySort(PropertyDescriptor property, ListSortDirection direction)
at System.Windows.Forms.DataGridView.DataGridViewDataConnection.Sort(DataGridViewColumn dataGridViewColumn, ListSortDirection direction)
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.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
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