winform datagridview中combobox列改变选项时触发其他列变化

private void materialCheckGridView_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    int cidx = materialCheckGridView.CurrentCell.ColumnIndex;
    if (materialCheckGridView.Columns[cidx].Name == "ColRetMainDefect")
    {
        //还原控件并绑定事件
        ((ComboBox)e.Control).SelectedIndexChanged += new EventHandler(MaterialCheckForm_SelectedIndexChanged);
    }
}

private void MaterialCheckForm_SelectedIndexChanged(object sender, EventArgs e)
{
    int cindex = materialCheckGridView.CurrentRow.Index;
    if (cindex >= 0)
    {
        int idx = materialCheckGridView.CurrentCell.ColumnIndex;
        if (materialCheckGridView.Columns[idx].HeaderText == "回修主要病疵")
        {
            //int cindex = materialCheckGridView.CurrentCell.RowIndex;
            string defdesc = ProdReportDA.GetDefectsDescription(materialCheckGridView.Rows[cindex].Cells["ColRetMainDefect"].EditedFormattedValue.ToString(), materialCheckGridView.Rows[cindex].Cells["RollId"].Value.ToString());
            materialCheckGridView.Rows[cindex].Cells["ColDefectDesc"].Value = defdesc;
        }
    }
}