private EOLPDBEntities _db;

       private string entityConnectionString = ConfigurationManager.ConnectionStrings["EOLPDBEntities"].ConnectionString;//獲取App.Config裡的連結字串

       public EOLPDBEntities GetMyTestEntityNew(string database,string SID)//傳兩個值，用來做修改的引數
       {

           var ecsb = new EntityConnectionStringBuilder(entityConnectionString);

           var scsb = new SqlConnectionStringBuilder(ecsb.ProviderConnectionString);

           scsb.InitialCatalog = database;//在此修改引數
           scsb.DataSource = SID;;//在此修改引數 

           ecsb.ProviderConnectionString = scsb.ToString();

           _db = new EOLPDBEntities(ecsb.ToString());
          
           return _db;  返回一個數據集

       }

  使用時  private EOLPDBEntities eolpDB = Conntronstr.GetConnEOLPDBEntities();

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