须撤销动态事件 combox.SelectedIndexChanged -= new EventHandler(Comb

时间:2022-02-19 08:08:28

问题:DataGridView绑定数据源之后,有一列需要用下拉框DataGridViewComboBoxCell显示,但是在措置惩罚惩罚DataGridViewComboBoxCell的下拉事件有些麻烦,它不像ComBox有SelectedIndexChanged,困扰我很久,结合网上的一些要领,再加上本身的一些窜改,终于完全可以解决这个问题了。下面是我的代码,有详细注释。

一、

        /// <summary>
        /// 首先给这个DataGridView加上EditingControlShowing事件
        /// </summary>
        /// <param></param>
        /// <param></param>

public void dgv_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
        {
            DataGridView dgv = sender as DataGridView;

//判断相应的列
            if (dgv.CurrentCell.GetType().Name == "DataGridViewComboBoxCell" && dgv.CurrentCell.RowIndex != -1)
            {

//给这个DataGridViewComboBoxCell加上下拉事件
                (e.Control as ComboBox).SelectedIndexChanged += new EventHandler(ComboBox_SelectedIndexChanged);
               
            }
        }

二、

/// <summary>
        /// 组合框事件措置惩罚惩罚
        /// </summary>
        /// <param></param>
        /// <param></param>
        public void ComboBox_SelectedIndexChanged(object sender, EventArgs e)
        {

ComboBox combox=sender as ComboBox;

 //这里对照重要
            combox.Leave+=new EventHandler(combox_Leave);
             try
             {
                 //在这里就可以做值是否转变判断
                 if (combox.SelectedItem != null)
                 {
                     
                 }
                 Thread.Sleep(100);
             }
             catch (Exception ex)
             {
                 MessageBox.Show(ex.Message);
             }
        }

三、(这一步对照重要,如果不加,会导致selectedchanged事件一直触发

/// <summary>
        /// 分开combox时,把事件删除
        /// </summary>
        /// <param></param>
        /// <param></param>
        public void combox_Leave(object sender, EventArgs e)
        {
            ComboBox combox = sender as ComboBox;
            //做完措置惩罚惩罚,须勾销动态事件
            combox.SelectedIndexChanged -= new EventHandler(ComboBox_SelectedIndexChanged);
        }

总结:网上的要领一般都是在第二步的时候把

//做完措置惩罚惩罚,,须勾销动态事件
            combox.SelectedIndexChanged -= new EventHandler(ComboBox_SelectedIndexChanged);