dataGridView ComboBox事件处理程序问题

Question

我在处理驻留在dataGridView中的comboBox的索引更改事件时遇到问题.我编写了一个方法来使用委托来处理comboBox选择更改:

ComboBox.SelectedIndexChanged -= delegate { ComboBoxIndexChanged(); };
ComboBox.SelectedIndexChanged += delegate { ComboBoxIndexChanged(); };

或者一个EventHandler:

comboBox.SelectedIndexChanged += new EventHandler(ComboBoxIndexChanged);

但这两种方法都没有按预期工作.也就是说,当您在comboBox中单击您的选择(包含在dataGridView中)时,需要多次单击才能生成我的ComboBoxIndexChanged(); 正常运行的方法,如果它决定完全起作用.克服/关于在dataGridView中的comboBox的indexedChange上指定事件的最佳方法是什么？

我目前在上下文中使用的代码如下:

private void dataGridView_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    try
    {
        if (this.dataGridView.CurrentCell.ColumnIndex == (int)Column.Col)
        {
            ComboBox comboBox = e.Control as ComboBox;
            if (comboBox != null)
            {
                comboBox.SelectedIndexChanged += new EventHandler(ComboBoxIndexChanged);
            }
        }
        return;
    }
    catch (Exception Ex)
    {
        Utils.ErrMsg(Ex.Message);
        return;
    }
}

并且事件ComboBoxIndexChanged是:

private void ComboBoxIndexChanged(object sender, EventArgs e)
{
    // Do some amazing stuff...
}

我已经在StackOverFlow上读了一个类似的线程,该线程表明以这种方式处理comboBox更改事件存在问题,但我无法使解决方案起作用.可以在此处找到帖子:Datagridview上的ComboBoxColumn中的"SelectedIndexChanged"事件.它说:

"事情变得复杂,因为他们通过对所有行只有一个编辑控件来优化DataGridView.这就是我处理类似情况的方式:

首先将委托连接到EditControlShowing事件:

myGrid.EditingControlShowing += new DataGridViewEditingControlShowingEventHandler(
                                Grid_EditingControlShowing);
...

然后在处理程序中,连接到EditControl的SelectedValueChanged事件:

void Grid_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    ComboBox combo = e.Control as ComboBox;
    if (combo != null)
    {
        // the event to handle combo changes
        EventHandler comboDelegate = new EventHandler(
          (cbSender, args) =>
            {
                DoSomeStuff();
            });

        // register the event with the editing control
        combo.SelectedValueChanged += comboDelegate;

        // since we don't want to add this event multiple times, when the 
        // editing control is hidden, we must remove the handler we added.
        EventHandler visibilityDelegate = null;
        visibilityDelegate = new EventHandler(
          (visSender, args) =>
            {
                // remove the handlers when the editing control is
                // no longer visible.
                if ((visSender as Control).Visible == false)
                {
                    combo.SelectedValueChanged -= comboDelegate;
                    visSender.VisibleChanged -= visibilityDelegate;
                }
            });

         (sender as DataGridView).EditingControl.VisibleChanged += 
           visibilityDelegate;
    }
}"

我对此的这个问题是没有定义"VisSender",因此无法使用"VisibleChanged"事件.

你小伙子的任何帮助,一如既往,最受赞赏.

Answer 1

听起来您希望在用户更改下拉框后立即提交更改,而无需单击单元格.为了做到这一点,您需要在发生更改时强制提交(使用CommitEdit,MSDN页面上也有一个示例).将此添加到您的DataGridView:

// This event handler manually raises the CellValueChanged event
// by calling the CommitEdit method.
void dataGridView1_CurrentCellDirtyStateChanged(object sender,
    EventArgs e)
{
    if (dataGridView1.IsCurrentCellDirty)
    {
        dataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit);
    }
}

然后你可以只听,CellValueChanged并避免必须尝试在底层编辑控件上注册ComboBoxValueChanged事件.