当更改CheckBox是空格键时，AcceptChanges（）会抛出异常 [英] AcceptChanges() throws exception when changing CheckBox is with space bar

问题描述

在我的 DataGridView 中，我使用DataView过滤DataTable。在过滤器中使用 CheckBox 值。

In my DataGridView I use a DataView to filter the DataTable. The CheckBox value is used in the filter.

当复选框未被选中时，行应该消失。要立即运行，我在 CurrentCellDirtyStateChanged 事件中使用 AcceptChanges（）。 （否则行保持显示，直到选择另一行）。

When the CheckBox is unchecked, the row should disappear. To run that immediately, I use AcceptChanges() in an CurrentCellDirtyStateChanged event. (Otherwise the row stays displayed, until another row is selected).

当我用鼠标取消选中该复选框时，这可以工作。 使用空格键将抛出 NullReferenceException 异常。

以下是一些示例代码：

（完全正常工作，只需要一个空格为DataGridView1的Form1，用空格键更改复选框会引发异常）

(Full working. Needs only Form1 with a blank DataGridView1. Changing the CheckBox with space bar throws the exception)

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        DataTable table;
        DataView view; 

        public Form1()
        {
            InitializeComponent();

            Init();
        }

        // Building the table and view
        private void Init()
        {
            table = new DataTable();
            table.Columns.Add("check", typeof(bool));

            table.Rows.Add(true);
            table.Rows.Add(true);
            table.Rows.Add(true);

            view = new DataView(table);
            view.RowFilter = "check = true";

            dataGridView1.DataSource = view;
        }

        // CurrentCellDirtyStateChanged Event
        private void dataGridView1_CurrentCellDirtyStateChanged(object sender, EventArgs e)
        {
            if (dataGridView1.IsCurrentCellDirty == true && dataGridView1.CurrentCell is DataGridViewCheckBoxCell)
            {
                dataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit);

                // AcceptChanges to update the view
                // works with mouse click, throws NullReferenceException when spacebar is used
                table.AcceptChanges();
            }
        }
    }
}

有没有办法使它与空格键一起工作？

Is there any way make it working with the space bar also?

修改

异常被抛出在.net运行时，而不是直接由AcceptChanges（）

Edit
The exception is thrown anywhere in the .net runtime and not directly by AcceptChanges()

System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
     bei System.Windows.Forms.DataGridViewCheckBoxCell.NotifyMASSClient(Point position)
     bei System.Windows.Forms.DataGridViewCheckBoxCell.OnKeyUp(KeyEventArgs e, Int32 rowIndex)
     bei System.Windows.Forms.DataGridView.OnKeyUp(KeyEventArgs e)
     bei System.Windows.Forms.Control.ProcessKeyEventArgs(Message& m)
     bei System.Windows.Forms.DataGridView.ProcessKeyEventArgs(Message& m)
     bei System.Windows.Forms.Control.WmKeyChar(Message& m)
     bei System.Windows.Forms.Control.WndProc(Message& m)
     bei System.Windows.Forms.DataGridView.WndProc(Message& m)
     bei System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
     bei System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
     bei System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
     bei System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
     bei System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
     bei Sample.Program.Main() in C:\Projects\TFS\Sample\Sample\Program.cs:Zeile 21.

推荐答案

如 Microsoft Connect 一个潜在的解决方法是延迟 CommitEdit 直到 CellDirtyStateChanged 事件处理程序完成。

As reported on Microsoft Connect a potential workaround is to delay CommitEdit until CellDirtyStateChanged event handler completes.

public delegate void InvokeDelegate();

public void MyDelegate()
{
    dataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit);
    table.AcceptChanges();
}

//CurrentCellDirtyStateChanged Event
private void dataGridView1_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
    if (dataGridView1.IsCurrentCellDirty == true && dataGridView1.CurrentCell is DataGridViewCheckBoxCell)
    {
        BeginInvoke(new InvokeDelegate(MyDelegate));
    }
}

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