public partial class Model1 : DbContext

    {

        private static string connStr = "";

        public Model1() : base("Data Source=.;Initial Catalog=GameDb;user id=sa;password=123456")//默认随便填一个标准连接字符串，如果不是标准的你的后面设置连接字符串会出错，具体原因大家有兴趣的去深究吧

        {if (connStr == "")

            {

                connStr = ConfigurationManager.ConnectionStrings["Model1"].ConnectionString;

                connStr = SymmetricMethod.Decrypto(connStr);

            }

            base.Database.Connection.ConnectionString = connStr;

        }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)

        {

        }

    }

 <add name="Model1" connectionString="zgtsMV7VlXojlkp2VhEQvCsN6Pq/RsadZKfvOgqRWKPtBL8/x+2yBuSiWjfkMueEcAbFVTrI094JVLn28NnyiHlAqUl8q8g4T/ybEi4gPQPVEdUfg31xF8NLgWDCAGR9Tw+7/VTm/WRpBHxrpCwUwggB35QNgqkXo+1SQ6OmpqhrNdSuPrlzh1UoOHP/p55WrVL2TNOZ5n4v6CUmODdTVw==" providerName="System.Data.SqlClient" />

  </connectionStrings>