SqlHelper

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Configuration;
 6 using System.Data.SqlClient;
 7 using System.Data;
 8 
 9 namespace ADONET2
10 {
11     class SqlHelper
12     {
13         private static string connStr = ConfigurationManager.ConnectionStrings["dbConnStr"].ConnectionString;
14 
15         public static int ExecuteNonQuery(string sql)
16         {
17             using (SqlConnection conn = new SqlConnection(connStr))
18             {
19                 conn.Open();
20                 using (SqlCommand cmd = conn.CreateCommand())
21                 {
22                     cmd.CommandText = sql;
23                     return cmd.ExecuteNonQuery();//返回值代表影响了多少行数据
24                 }
25             }
26         }
27 
28         public static object ExecuteScalar(string sql)
29         {
30             using (SqlConnection conn = new SqlConnection(connStr))
31             {
32                 conn.Open();
33                 using (SqlCommand cmd = new SqlCommand())
34                 {
35                     cmd.CommandText = sql;
36                     return cmd.ExecuteScalar();
37                 }
38             }
39         }
40 
41         public static DataSet ExecuteDataSet(string sql)
42         {
43             using (SqlConnection conn = new SqlConnection(connStr))
44             {
45                 conn.Open();
46                 using (SqlCommand cmd = new SqlCommand(sql,conn))
47                 {
48                     //cmd.Connection = conn; /*不知道为什么必须要设置这个
49                     //cmd.CommandText = sql;
50                     SqlDataAdapter adapter = new SqlDataAdapter(cmd);
51                     DataSet dataset = new DataSet();
52                     adapter.Fill(dataset);
53                     return dataset;
54                 }
55             }
56         }
57     }
58 }

1 //SqlHelper的使用
2 
3 DataSet ds = SqlHelper.ExecuteDataSet("select * from T_Student");
4             foreach (DataRow row in ds.Tables[0].Rows)
5             {
6                 string name = (string)row["Name"];
7                 int age = (int)row["Age"];
8                 MessageBox.Show(name + "," + age);
9             }

posted on 2013-03-22 17:48 蘑菇蘑菇它不开花阅读(142) 评论(0) 编辑收藏举报