连接oracle 字符串问题

连接到自己的oracle数据库，我用的字符串如

System.Data.OracleClient.OracleConnection conn=new OracleConnection();

conn.ConnectionString ="Data Source=(DESCRIPTION = (ADDRESS_LIST= (ADDRESS = (PROTOCOL = TCP)(HOST = zhulin1)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = orazl) ) );User Id=ems_user;Password=emssme";

编译时，在output窗口出现下面提示

Additional information: Invalid length for connection option 'data source', maximum length is 128.

不知道哪位兄弟能够解决这个问题，感谢！！