Question

我希望在ComboBox单元格中的DataGridView中更改值时处理该事件。

有CellValueChanged事件，但在我点击DataGridView内的其他地方之前，该事件才会触发。

选择新值后，会立即触发一个简单的ComboBox SelectedValueChanged。

如何将侦听器添加到单元格内的组合框？

Answer 1

上面的回答让我在报春花路上走了一段时间。它不起作用，因为它导致多个事件触发并且只是不断添加事件。问题是上面捕获DataGridViewEditingControlShowingEvent并且它没有捕获更改的值。因此，每次你聚焦时它都会触发，然后离开组合框，无论它是否已经改变。

关于“CurrentCellDirtyStateChanged”的最后一个答案是正确的方法。我希望这可以帮助别人避免陷入兔子洞。

这是一些代码。

        // 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 (this.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

这是代码，它将触发dataGridView中comboBox中的选择事件：

public Form1()
    {
        InitializeComponent();

        DataGridViewComboBoxColumn cmbcolumn = new DataGridViewComboBoxColumn();
        cmbcolumn.Name = "cmbColumn";
        cmbcolumn.HeaderText = "combobox column";
        cmbcolumn.Items.AddRange(new string[] { "aa", "ac", "aacc" });
        dataGridView1.Columns.Add(cmbcolumn);
        dataGridView1.EditingControlShowing += new DataGridViewEditingControlShowingEventHandler(dataGridView1_EditingControlShowing);
    }

    private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
    {
        ComboBox combo = e.Control as ComboBox;
        if (combo != null)
        {
            combo.SelectedIndexChanged -= new EventHandler(ComboBox_SelectedIndexChanged);
            combo.SelectedIndexChanged += new EventHandler(ComboBox_SelectedIndexChanged);
        }
    }

    private void ComboBox_SelectedIndexChanged(object sender, EventArgs e)
    {
        ComboBox cb = (ComboBox)sender;
        string item = cb.Text;
        if (item != null)
            MessageBox.Show(item);
    }

Answer 3

您还可以处理在值发生更改时调用的CurrentCellDirtyStateChanged事件，即使它未被提交。要获取列表中的选定值，您可以执行以下操作：

var newValue = dataGridView.CurrentCell.EditedFormattedValue;

Answer 4

我已经实施了另一种解决方案，它似乎比上面的 Mitja Bonca 的响应更快（例如，更快且点击次数更少）。虽然有时组合框会很快关闭。这使用 CurrentCellDirtyStateChanged 和 CellMouseDown 回调

private void myGrid_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
    if (myGrid.CurrentCell is DataGridViewComboBoxCell)
    {
        myGrid.CommitEdit(DataGridViewDataErrorContexts.Commit);
        myGrid.EndEdit();
    }
}

private void myGrid_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
{
    if (myGrid.Rows[e.RowIndex].Cells[e.ColumnIndex] is DataGridViewComboBoxCell)
    {
        myGrid.CurrentCell = myGrid.Rows[e.RowIndex].Cells[e.ColumnIndex];
        myGrid.BeginEdit(true);
        ((ComboBox)myGrid.EditingControl).DroppedDown = true; // Tell combobox to expand
    }
}

Answer 5

ComboBox cmbBox = (ComboBox)sender;                
MessageBox.Show(cmbBox.SelectedValue.ToString());

什么事件在DataGridViewCell中的组合框中捕获了值的变化？

5 个答案: