.andSelf()

.live()

.die()

.error()

.load()

.unload()

.size()

.toggle()

app.UseStaticFiles(new StaticFileOptions

{

    OnPrepareResponse = ctx =>

    {

        const int durationInSeconds = 60 * 60 * 24 * 365; //一年

        ctx.Context.Response.Headers[HeaderNames.CacheControl] =

            "public,max-age=" + durationInSeconds;

    }

});



app.UseRouting();

<a href="http://..." target="_blank" rel="opener">Link</a>

$(".hlkPrint").click(function () {

    $("form").setPostDataToStorage();



    $("form").attr("rel", "opener");

    $("form").attr("target", "_blank");

    $("form").attr("action", "xxxxx.aspx");

    $("form").submit();

}); 

-- 假設 OrderDetailId 是 varchar(20)

-- OrderDetail 有千萬筆資料



Select * from OrderDetail where OrderDetailId= N'20220923084533'

-- 結果跑超級久 (未使用 PK 找，掃整個 table)

Select * from OrderDetail where OrderDetailId= '20220923084533'

-- 結果一下就出來 (使用 PK 找)

-- **資料庫設計最好以數值來當 key 比較好

var newFilename = filename.Replace("..", "").ValidFilenameCharacters();

        static System.Security.Cryptography.RandomNumberGenerator RandomNumberGenerator = null;



        /// <summary>

        /// 回傳大於等於 0 小於 1

        /// </summary>

        /// <returns></returns>

        public static double NextDouble()

        {

            if (RandomNumberGenerator == null || LastRandomGenerateTime < DateTime.Now.AddMinutes(-1))

            {

                RandomNumberGenerator = System.Security.Cryptography.RandomNumberGenerator.Create();

            }



            // Generate four random bytes

            byte[] four_bytes = new byte[4];

            RandomNumberGenerator.GetBytes(four_bytes);



            // Convert the bytes to a UInt32

            uint scale = BitConverter.ToUInt32(four_bytes, 0);



            // And use that to pick a random number >= min and < max

            // 0 <= (scale / (uint.MaxValue + 1.0)) < 1

            return scale / (uint.MaxValue + 1.0);

        }



        /// <summary>

        /// 回傳值介於 min ~ (max - 1)

        /// </summary>

        /// <param name="min"></param>

        /// <param name="max"></param>

        /// <returns></returns>

        public static int GetRandomInt(int min, int max)

        {

            if(max < min)

            {

                throw new Exception("最大值不可小於最小值");

            }



            // Generate four random bytes

            byte[] four_bytes = new byte[4];

            RandomNumberGenerator.GetBytes(four_bytes);



            // And use that to pick a random number >= min and < max

            return (int)(min + (max - min) * NextDouble()); //因為 NextDouble 會小於 1，所以用無條件捨去.

        }



        /// <summary>

        /// 產生 0 ~ (max - 1) 的亂數

        /// </summary>

        /// <param name="max"></param>

        /// <returns></returns>

        public static int GetRandomInt(int max)

        {

            return GetRandomInt(0, max);

        }



        /// <summary>

        /// 產生 0 ~ (int.MaxValue - 1) 的亂數

        /// </summary>

        /// <returns></returns>

        public static int GetRandomInt()

        {

            return GetRandomInt(int.MaxValue);

        }