在DataGridViewComboBoxColumn SelectedIndexChanged期间触发的事件

Question

我有两列DataGridView。第一列是TextBoxCol(DataGridViewTextBoxColumn)，第二列是ComboBoxCol(DataGridViewComboBoxColumn)。

当TextBoxCol更改其选定的索引值时，如何更改ComboBoxCol的值？ （当ComboBoxCol中的选定索引发生变化时，就会发生这种情况。离开列后不会发生，如dataGridView_CellValueChanged）

我已经阅读了一个与我遇到的问题几乎相同的主题，但我不明白答案（根据复选标记应该是正确的）。这是链接。 -Almost same topic

Answer 1

这个答案在几个地方浮动。使用DataGridViewEditingControlShowingEventHandler将触发比您想要的更多事件。在我的测试中，它多次触发了该事件。另外使用combo.SelectedIndexChanged - =事件不会真正删除事件，它们只是保持堆叠。无论如何，我找到了一个似乎有效的解决方案。我在下面提供了一个代码示例：

           // Add the events to listen for
        dataGridView1.CellValueChanged +=
             new DataGridViewCellEventHandler(dataGridView1_CellValueChanged);
        dataGridView1.CurrentCellDirtyStateChanged +=
             new EventHandler(dataGridView1_CurrentCellDirtyStateChanged);

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

    private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {
        // My combobox column is the second one so I hard coded a 1, flavor to taste
        DataGridViewComboBoxCell cb = (DataGridViewComboBoxCell)dataGridView1.Rows[e.RowIndex].Cells[1];
        if (cb.Value != null)
        {
               // do stuff
               dataGridView1.Invalidate();
        }
     }

Answer 2

给出这两个简单的方法（top方法中的'1'是组合框列的索引）

您可以修改的行是设置行cel.Value =，因为您可以将其更改为您喜欢的任何内容。

---

    private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
    {
        if (dataGridView1.CurrentCell.ColumnIndex == 1 && e.Control is ComboBox)
        {
            ComboBox comboBox = e.Control as ComboBox;
            comboBox.SelectedIndexChanged -= LastColumnComboSelectionChanged;
            comboBox.SelectedIndexChanged += LastColumnComboSelectionChanged;
        }
    }

    private void LastColumnComboSelectionChanged(object sender, EventArgs e)
    {
        var currentcell = dataGridView1.CurrentCellAddress;
        var sendingCB = sender as DataGridViewComboBoxEditingControl;
        DataGridViewTextBoxCell cel = (DataGridViewTextBoxCell)dataGridView1.Rows[currentcell.Y].Cells[0];
        cel.Value = sendingCB.EditingControlFormattedValue.ToString();
    }

---

Answer 3

该链接是正确的。处理DataGridView的EditingControlShowing event。在此事件处理程序中，检查当前列是否符合您的兴趣。然后，创建一个临时组合框对象： -

ComboBox comboBox = e.Control as ComboBox;

MSDN有一个示例：请参阅示例部分here。 请注意 Inheritance Hierarchy＆amp; msdn链接中的Class Syntax： -

  

公共类DataGridViewComboBoxEditingControl： ComboBox ，     IDataGridViewEditingControl

private DataGridView dataGridView1 = new DataGridView();

private void AddColorColumn()
{
    DataGridViewComboBoxColumn comboBoxColumn =
        new DataGridViewComboBoxColumn();
    comboBoxColumn.Items.AddRange(
        Color.Red, Color.Yellow, Color.Green, Color.Blue);
    comboBoxColumn.ValueType = typeof(Color);
    dataGridView1.Columns.Add(comboBoxColumn);
    dataGridView1.EditingControlShowing +=
        new DataGridViewEditingControlShowingEventHandler(
        dataGridView1_EditingControlShowing);
}

private void dataGridView1_EditingControlShowing(object sender,
    DataGridViewEditingControlShowingEventArgs e)
{
    ComboBox combo = e.Control as ComboBox;
    if (combo != null)
    {
        // Remove an existing event-handler, if present, to avoid 
        // adding multiple handlers when the editing control is reused.
        combo.SelectedIndexChanged -=
            new EventHandler(ComboBox_SelectedIndexChanged);

        // Add the event handler. 
        combo.SelectedIndexChanged +=
            new EventHandler(ComboBox_SelectedIndexChanged);
    }
}

private void ComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
    ((ComboBox)sender).BackColor = (Color)((ComboBox)sender).SelectedItem;
}