Sqlite日期查询

 /// <summary>
        /// 按日期查询
        /// </summary>
        private string QueryByDate()
        {
            string date1 = this.inquirePage.dateTimePicker1.SelectedDate?.ToString("yyyy-M-dd HH:mm:ss");
            DateTime temp1;
            DateTime temp2;
            string date2 = string.Empty;
            if (this.inquirePage.dateTimePicker2.SelectedDate != null)
            {
                temp1 = this.inquirePage.dateTimePicker2.SelectedDate.Value;
                temp2 = new DateTime(temp1.Date.Year, temp1.Date.Month, temp1.Date.Day, 23, 59, 59);
                date2 = temp2.ToString("yyyy-M-dd HH:mm:ss");
            }
            if (date1 == null || date2.Equals(string.Empty))
            {
                MessageBox.Show("时间格式错误!");
                return string.Empty;
            }
            string sql = "select * from BatchNumberInfo where Start_Time > '" + date1 + "' and End_Time < '" + date2 + " '";
            return sql;
 
        }