\network\ADMIN\tnsnames.ora

# ---------------------------------------------
   PORTAL = 
   (DESCRIPTION = 
   (ADDRESS_LIST = 
   (ADDRESS = (PROTOCOL = TCP)(HOST = 134.104.52.6)(PORT = 1521)) 
   ) 
   (CONNECT_DATA = 
   (SERVICE_NAME = portal) 
   ) 
   )

*/ 
   public static string[] GetOracleTnsNames() 
   { 
   try 
   { 
   // 查询注册表，获取oracle服务文件路径 
   RegistryKey key = Registry.LocalMachine.OpenSubKey("SOFTWARE").OpenSubKey("ORACLE"); 
   string home = (string)key.GetValue("ORACLE_HOME"); 
   string file = home + @"\network\ADMIN\tnsnames.ora"; 
   
   // 解析文件 
   string line; 
   ArrayList arr = new ArrayList(); 
   StreamReader sr = new StreamReader(file); 
   while ((line = sr.ReadLine()) != null) 
   { 
   line = line.Trim(); 
   if (line != "") 
   { 
   char c = line[0]; 
   if ( c>= 'A' && c<='z') 
   arr.Add(line.Substring(0, line.IndexOf(' '))); 
   } 
   } 
   sr.Close(); 
   
   // 返回字符串数组 
   return (string[])arr.ToArray(typeof(string)); 
   } 
   catch (Exception ex) 
   { 
   return null; 
   } 
   }