跟着教程做网站时的一个DBHelper的小例子。记下来说不定以后用得上。
1 using System;
2 using System.Collections.Generic;
3 using System.Text;
4 using System.Data;
5 using System.Data.SqlClient;
6 using System.Configuration;
7
8
9 namespace PracticeMyBookShopDAL
10 {
11 public static class DBHelper
12 {
13
14 private static SqlConnection connection;
15 public static SqlConnection Connection
16 {
17 get
18 {
19 string connectionString = "Data Source=ADMIN-PC;Initial Catalog=MyBookShop;Integrated Security=True";
20 if (connection == null)
21 {
22 connection = new SqlConnection(connectionString);
23 connection.Open();
24 }
25 else if (connection.State == System.Data.ConnectionState.Closed)
26 {
27 connection.Open();
28 }
29 else if (connection.State == System.Data.ConnectionState.Broken)
30 {
31 connection.Close();
32 connection.Open();
33 }
34 return connection;
35 }
36 }
37
38 public static int ExecuteCommand(string safeSql)
39 {
40 SqlCommand cmd = new SqlCommand(safeSql, Connection);
41 int result = cmd.ExecuteNonQuery();
42 return result;
43 }
44
45 public static int ExecuteCommand(string sql, SqlParameter[] values)
46 {
47 SqlCommand cmd = new SqlCommand(sql, Connection);
48 cmd.Parameters.AddRange(values);
49 return cmd.ExecuteNonQuery();
50 }
51
52 public static int ExecuteCommand(string sql, SqlParameter value)
53 {
54 SqlCommand cmd = new SqlCommand(sql, Connection);
55 cmd.Parameters.Add(value);
56 int result = cmd.ExecuteNonQuery();
57 return result;
58 }
59
60
61 public static int ExecuteScalar(string safeSql)
62 {
63 SqlCommand cmd = new SqlCommand(safeSql, Connection);
64 int result = (int)cmd.ExecuteScalar();
65 return result;
66 }
67
68 public static int ExecuteScalar(string sql, SqlParameter[] values)
69 {
70 SqlCommand cmd = new SqlCommand(sql, Connection);
71 cmd.Parameters.AddRange(values);
72 int result = (int)cmd.ExecuteScalar();
73 return result;
74 }
75
76 public static int ExecuteScalar(string sql, SqlParameter value)
77 {
78 SqlCommand cmd = new SqlCommand(sql, Connection);
79 cmd.Parameters.Add(value);
80 int result = (int)cmd.ExecuteScalar();
81 return result;
82 }
83
84 public static SqlDataReader ExecuteReader(string safeSql)
85 {
86 SqlCommand cmd = new SqlCommand(safeSql, Connection);
87 SqlDataReader reader = cmd.ExecuteReader();
88 return reader;
89 }
90
91 public static SqlDataReader ExecuteReader(string sql, SqlParameter value)
92 {
93 SqlCommand cmd = new SqlCommand(sql, Connection);
94 cmd.Parameters.Add(value);
95 SqlDataReader reader = cmd.ExecuteReader();
96 return reader;
97 }
98
99 public static SqlDataReader ExecuteReader(string sql, SqlParameter[] values)
100 {
101 SqlCommand cmd = new SqlCommand(sql, Connection);
102 cmd.Parameters.AddRange(values);
103 SqlDataReader reader = cmd.ExecuteReader();
104 return reader;
105 }
106 public static DataTable GetDataSet(string safeSql)
107 {
108 DataSet ds = new DataSet();
109 SqlCommand cmd = new SqlCommand(safeSql, Connection);
110 SqlDataAdapter da = new SqlDataAdapter(cmd);
111 da.Fill(ds);
112 return ds.Tables[0];
113 }
114 public static SqlDataReader GetReader(string safeSql)
115 {
116 SqlCommand cmd = new SqlCommand(safeSql, Connection);
117 SqlDataReader reader = cmd.ExecuteReader();
118 return reader;
119 }
120
121 public static SqlDataReader GetReader(string sql, params SqlParameter[] values)
122 {
123 SqlCommand cmd = new SqlCommand(sql, Connection);
124 cmd.Parameters.AddRange(values);
125 SqlDataReader reader = cmd.ExecuteReader();
126 return reader;
127 }
128
129
130 }
131 }