以前年輕不懂事, 寫了一些很遜的程式碼, 例如:

舊的程式碼:

        public static DataTable DTFromSQL(string Sql, string DBC = null, Int32 timeout = 0)

        {

            SqlDataAdapter DA = new SqlDataAdapter(Sql, GetDBC(DBC));



            DataTable DT = new DataTable();

            try

            {

                DA = new SqlDataAdapter(Sql, DBC);

                if (timeout > 0)

                {

                    DA.SelectCommand.CommandTimeout = timeout;

                }



                DA.Fill(DT);

            }

            catch (Exception ex)

            {

                throw new Exception(ex.ToString());

            }

            finally

            {

                DA.Dispose();

            }



            return DT;

        }

新的程式碼:

        public static DataTable DTFromSQL(string Sql, string DBC = null, Int32 timeout = 30)

        {

            using (var DA = new SqlDataAdapter(Sql, GetDBC(DBC)))

            {

                //不可為 null

                DataTable DT = new DataTable();



                DA.SelectCommand.CommandTimeout = timeout;



                DA.Fill(DT);



                return DT;

            }

        }

可以參考:
https://dotblogs.com.tw/yc421206/archive/2012/01/03/64154.aspx
 

試分析以下兩個 function..

        public static void WriteText1(string FileName, List<string> ltData)

        {

            foreach(string data in ltData)

            {

                System.IO.File.AppendAllText(FileName, data);

            }

        }



        public static void WriteText2(string FileName, List<string> ltData)

        {

            var Res = "";

            foreach (string data in ltData)

            {

                Res += data;

            }



            System.IO.File.WriteAllText(FileName, Res);

        }

https://www.techrepublic.com/article/working-with-the-aspnet-globalasax-file/

Application_BeginRequest
Application_AuthenticateRequest
Application_AuthorizeRequest
Application_ResolveRequestCache
Application_AcquireRequestState
Application_PreRequestHandlerExecute
Application_PreSendRequestHeaders
Application_PreSendRequestContent
<<code is executed>>
Application_PostRequestHandlerExecute
Application_ReleaseRequestState
Application_UpdateRequestCache
Application_EndRequest

抓出每個 Block_Id 中, End_Date 最小的資料.

語法 A:
With TempBlock as (
Select *, 
ROW_NUMBER() OVER(PARTITION BY B.Block_Id ORDER BY B.End_Date, B.Id) AS rk 
from BlockData B Where IsDelete = 'N' and End_Date >= getDate())
Select * from TempBlock Where rk = 1

語法 B:
Select * from (
Select *, 
ROW_NUMBER() OVER(PARTITION BY B.Block_Id ORDER BY B.End_Date, B.Id) AS rk 
from BlockData B Where IsDelete = 'N' and End_Date >= getDate()) TempBlock 
Where rk = 1

Visual Studio 預設發佈的模式是不包括錯誤行號的. 要開啟在這裡設定:



還有 option 要設定:

 
 

想到的先列出來.

1. 幫 String 擴充屬性(javascript, .NET)
2. SQL Injection.
3. Cross Site Script Attack.
4. 避免排程未完全執行以及重覆執行.
5. 更新 Cache 與 Lock.
6. SQL Transaction.
 

lock 的 object 和 cachename 最好是相關的.

ex: lock (S3.LockObjs.GetLockerObject(CacheName))

內容後補..

不要自動加 "s"

 

先留個言, 有空來補內容.

VB
Public Module SqlStringExtention

    <Extension()>
    Function SQLStr(ByVal Original As String) As String
        Return Original.Replace("'", "''")
    End Function

    <Extension()>
    Function SQLTrim(ByVal Original As String) As String
        Return Original.Trim.Replace("'", "''")
    End Function

End Module

C#
//Extension methods must be defined in a static class
    public static class StringExtension
    {
        /// <summary>
        /// 把 ' 取代成 ''
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        public static string sqlStr(this string value)
        {
            return value.Replace("'", "''");
        }

        /// <summary>
        /// 假設欄位名稱中不會有 [ 或 ] 的符號
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        public static string sqlField(this string value)
        {
            return "[" + value.Replace("[", "").Replace("]", "") + "]";
        }
    }

LEN: 不會計入空白結尾. DATALENGTH: 實際的長度.