Windows窗体应用程序异常

Question

我收到申请异常

   at System.Windows.Forms.CurrencyManager.get_Item(Int32 index)
   at System.Windows.Forms.CurrencyManager.get_Current()
   at System.Windows.Forms.DataGridView.DataGridViewDataConnection.OnRowEnter(DataGridViewCellEventArgs e)
   at System.Windows.Forms.DataGridView.OnRowEnter(DataGridViewCell& dataGridViewCell, Int32 columnIndex, Int32 rowIndex, Boolean canCreateNewRow, Boolean validationFailureOccurred)
   at System.Windows.Forms.DataGridView.SetCurrentCellAddressCore(Int32 columnIndex, Int32 rowIndex, Boolean setAnchorCellAddress, Boolean validateCurrentCell, Boolean throughMouseClick)
   at System.Windows.Forms.DataGridView.OnCellMouseDown(HitTestInfo hti, Boolean isShiftDown, Boolean isControlDown)
   at System.Windows.Forms.DataGridView.OnCellMouseDown(DataGridViewCellMouseEventArgs e)
   at System.Windows.Forms.DataGridView.OnMouseDown(MouseEventArgs e)
   at System.Windows.Forms.Control.WmMouseDown(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(IntPtr 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(Form mainForm)
   at MedForms.Program.Main() in F:\Projects\Vstu\MedForms\MedForms\Program.cs:line 18
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly 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, Boolean ignoreSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

每次我尝试单击 DataGridView 时。

我收到错误消息

{“索引-1没有值。”} （SystemIndexOutOfaRange 异常）。

在行

Application.Run(new MainForm());

而且我无法调试它。请帮助我找出导致此类问题的原因以及如何调试它？

Answer 1

我猜测您已将一个最初为空的列表（或其他类型的不会生成列表更改事件的集合）绑定到您的

DataGridView

，然后将项目添加到此列表中。

您添加的项目将在网格上正确显示，但单击一行将导致此异常。这是因为底层 CurrencyManager 将报告其当前行位置为 -1 的偏移量。它将保持这种状态，因为列表不会向网格报告更改。

仅当列表中一开始就有一些项目时，才应将列表绑定到网格，或者在添加它们时重新绑定。

另请参阅我对

this

问题的回答，这本质上是同一个问题。

Answer 2

private List<Employee> Employees { get; set; } = new List<Employee>();
_employeesGridView.DataSource = Employees;

与

private BindingList<Employee> Employees { get; set; } = new BindingList<Employee>();
_employeesGridView.DataSource = Employees;

问题就消失了。

Answer 3