sqlite 中字符串比较

Question

hi,

我想要比较在sqlite某个表中，找出比参数string小的string。

但是下面这种写法在运行时，会提示SQLITE.cs中public static IntPtr Prepare2 (IntPtr db, string query)方法找不到compareto，

求助有什么好的解决方案么。

public async Task<List<mail_list>> SelectTime(string time)
        {
            try
            {
                if (connAsync == null)
                {
                    connAsync = new SQLiteAsyncConnection(strDbPath);
                }

                var query = connAsync.Table<mail_list>().Where(ml => (ml.sent_time.CompareTo(time)<0));

                List<mail_list> ls = await query.ToListAsync();
                return ls;
            }
            catch
            {
                return null;
            }
        }