我是一名新秀,刚学C#,在连接数据库的时候老师出错,望指点,连接代码如下:
 SqlConnection thisConnection = new SqlConnection(
                @"Server=(local);Integrated Security=True;" +
                "Database=northwind");
            //打开连接
            thisConnection.Open();
            //创建命令
            SqlCommand thisCommand = thisConnection.CreateCommand();
            //查询语句
             =
                "SELECT CustomerID ,CompanyName from Customers";
            //执行DataReader
            SqlDataReader thisReader = thisCommand.ExecuteReader();
            //while there are rows to read
            while (thisReader.Read())
            {
                //输出ID 和 NAME 行
                Console.WriteLine("\t{0}\t{1}",
                    thisReader["CustomerID"], thisReader["CompanyName"]);
            }
            //关闭 Reader
            thisReader.Close();
            //关闭连接
            thisConnection.Close();
            Console.WriteLine("Programe finished ,press enter/return to continue");
            Console.ReadKey();

连接串有应该还要给出密码的吧

还有就是数据库的服务器最好是明确的IP地址，这样比较好一些。

SqlConnection thisConnection = new SqlConnection(
                @"Data Source=(local);Integrated Security=True;" +
                "Database=northwind");
或者
sqlconnection conn=new sqlconnectin(@"server=(local);uid=sa;pwd=;database=northwind");

SqlConnection con=new SqlConnection("server=.;database=northwind;uid=sa;pwd=123456")

Server=(local);Integrated Security=True;Database=northwind;uid=用户名；pwd=密码