接口在ADO.NET中的应用(2)

 7
 8 namespace IFADO
 9
10 {
11     class Program
12     {
13         static void Main(string[] args)
14         {
15             string conStr = ConfigurationManager.ConnectionStrings["conStr"].ConnectionString;
16             string privider = ConfigurationManager.ConnectionStrings["conStr"].ProviderName;
17             IDbConnection conn;
18             switch (privider)
19             {
20                 case "Access": conn = new OleDbConnection(conStr); break;
21
22                 case "SQLSever": conn = new SqlConnection(conStr); break;
23
24                 case "Oracle": conn = new OracleConnection(conStr); break;
25
26                 default: throw new Exception("未找到合适的数据库，请扩展！);
27             }
28           using(conn)
29
30           {
31                 conn.Open();
32                 using (IDbCommand cmd = conn.CreateCommand())
33                 {
34                     cmd.CommandText = "SELECT * FROM Test_TableORDER BY Test_Table.ID DESC";
35
36                     cmd.ExecuteNonQuery();
37                 }
38                 Console.WriteLine("完成查询！");
39
40                 Console.ReadKey();
41             }