我試圖從文本框中獲取日期時間，它已經準備好了 MySql 日期時間的格式。DB中的列也是DateTime格式。但是，當我按下按鈕將日期保存在數據庫中時，整行將被清空。我在數據庫中嘗試了不同的格式和數據類型，沒有任何效果private void button4_Click(object sender, EventArgs e){    MySqlConnection conn = DBUtils.GetDBConnection();    conn.Open();    string startzeit = textBoxstartzeit.Text.ToString();    DateTime start = DateTime.Parse(startzeit);     string stopzeit = textBoxstopzeit.Text.ToString();    DateTime stop = DateTime.Parse(stopzeit);    string pstartzeit = textBoxstopzeit.Text.ToString();    DateTime pstart = DateTime.Parse(pstartzeit);    string pstopzeit = textBoxstopzeit.Text.ToString();    DateTime pstop = DateTime.Parse(pstopzeit);    MySqlCommand cmdnew = conn.CreateCommand();    cmdnew.CommandType = CommandType.Text;    cmdnew.CommandText = "UPDATE arbeitszeiten SET astart = '" + start + "',  astop = '" + stop + "', pstart = '" + pstart + "', pstop = '" + pstop + "' WHERE id = '" + dataGridView.CurrentCell.Value + "'";    cmdnew.ExecuteNonQuery();    conn.Close();}private void dataGridView_CellClick(object sender, DataGridViewCellEventArgs e){    try    {        MySqlConnection conn = DBUtils.GetDBConnection();        conn.Open();        MySqlCommand feedstartzeit = conn.CreateCommand();        feedstartzeit.CommandText = "SELECT astart FROM arbeitszeiten WHERE id = '" + dataGridView.CurrentCell.Value + "'";        DateTime start = Convert.ToDateTime(feedstartzeit.ExecuteScalar());        textBoxstartzeit.Text = start.ToString("yyyy-MM-dd HH:mm:ss");    }    catch (Exception ex)    {        MessageBox.Show(ex.Message, "Bitte ID ausw?hlen", MessageBoxButtons.OK, MessageBoxIcon.Error);    }}Button4 是上傳新數據，dataGridView 部分用預先格式化的日期時間填充文本框，稍后由 Button4 上傳