C# DBHelper 第二版
Posted fightingyy
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了C# DBHelper 第二版相关的知识，希望对你有一定的参考价值。
1. [代码][C#]代码 跳至 [1] [全屏预览]
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
|
/******************************** * Produce: DbHelper * Version: beta 2 * Date: 2012.10.11 ********************************/using System;using System.Data;using System.Data.SqlClient;using System.Configuration;using System.Collections.Generic;namespace DbHelper{ public class SqlDbHelper :IDisposable { protected SqlConnection conn; protected SqlCommand cmd; protected SqlDataReader reader; protected SqlDataAdapter adapter; protected string connectionString = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString; public static SqlDbHelper Instance = null; public string ConnectionString { get { return this.connectionString; } set { this.connectionString = value; } } static SqlDbHelper() { SqlDbHelper.Instance = new SqlDbHelper(); } /// <summary> /// 获取一个未打开连接的SqlConnection对象 /// </summary> /// <returns>SqlConnection对象</returns> public SqlConnection GetConnection() { if (conn != null) return this.conn; return this.conn = new SqlConnection(connectionString); } /// <summary> /// 使用连接字符串获取未打开连接SqlConnection对象 /// </summary> /// <param name="_connStr">连接字符串</param> /// <returns>SqlConnection对象</returns> public SqlConnection GetConnection(string _connStr) { if (this.conn != null) this.conn.ConnectionString = _connStr; else this.conn = new SqlConnection(_connStr); return this.conn; } /// <summary> /// 使用指定的Sql语句创建SqlCommand对象 /// </summary> /// <param name="sqlStr">Sql语句</param> /// <returns>SqlCommand对象</returns> private SqlCommand GetCommand(string sqlStr) { if (this.conn == null) this.conn = GetConnection(); if (this.cmd == null) this.cmd = this.GetCommand(sqlStr, CommandType.Text, null); else { this.cmd.CommandText = sqlStr; this.cmd.CommandType = CommandType.Text; this.cmd.Parameters.Clear(); } return this.cmd; } /// <summary> /// 使用指定的Sql语句,CommandType,SqlParameter数组创建SqlCommand对象 /// </summary> /// <param name="sqlStr">Sql语句</param> /// <param name="type">命令类型</param> /// <param name="paras">SqlParameter数组</param> /// <returns>SqlCommand对象</returns> public SqlCommand GetCommand(string sqlStr, CommandType type, SqlParameter[] paras) { if (conn == null) this.conn = this.GetConnection(); if (cmd == null) this.cmd = conn.CreateCommand(); this.cmd.CommandType = type; this.cmd.CommandText = sqlStr; this.cmd.Parameters.Clear(); if (paras != null) this.cmd.Parameters.AddRange(paras); return this.cmd; } /// <summary> /// 执行Sql语句返回受影响的行数 /// </summary> /// <param name="sqlStr">Sql语句</param> /// <returns>受影响的行数,失败则返回-1</returns> public int ExecuteNonQuery(string sqlStr) { int line = -1; try { line = this.ExecuteNonQuery(sqlStr,CommandType.Text,null); } catch (SqlException e) { throw e; } return line; } /// <summary> /// 使用指定的Sql语句,CommandType,SqlParameter数组执行Sql语句,返回受影响的行数 /// </summary> /// <param name="sqlStr">Sql语句</param> /// <param name="type">命令类型</param> /// <param name="paras">SqlParameter数组</param> /// <returns>受影响的行数</returns> public int ExecuteNonQuery(string sqlStr, CommandType type, SqlParameter[] paras) { int line = -1; CheckArgs(sqlStr); if (this.cmd == null) GetCommand(sqlStr, type, paras); this.cmd.Parameters.Clear(); this.cmd.CommandText = sqlStr; this.cmd.CommandType = type; if(paras != null) this.cmd.Parameters.AddRange(paras); try { OpenConn(); line = this.cmd.ExecuteNonQuery(); } catch (SqlException e) { throw e; } return line; } /// <summary> /// 使用指定Sql语句获取dataTable /// </summary> /// <param name="sqlStr">Sql语句</param> /// <returns>DataTable对象</returns> public DataTable GetDataTable(string sqlStr) { CheckArgs(sqlStr); if (this.conn == null) this.conn = GetConnection(); this.adapter = new SqlDataAdapter(sqlStr, this.conn); DataTable table = new DataTable(); try { adapter.Fill(table); } catch (SqlException e) { throw e; } finally { this.adapter.Dispose(); } return table; } /// <summary> /// 使用指定的Sql语句获取SqlDataReader /// </summary> /// <param name="sqlStr">sql语句</param> /// <returns>SqlDataReader对象</returns> public SqlDataReader GetSqlDataReader(string sqlStr) { CheckArgs(sqlStr); if (cmd == null) GetCommand(sqlStr); if(reader != null) reader.Dispose(); try { OpenConn(); this.reader = this.cmd.ExecuteReader(); } catch (SqlException e) { throw e; } return this.reader; } /// <summary> /// 使用事务执行多条Sql语句 /// </summary> /// <param name="sqlCommands">sql语句数组</param> /// <returns>全部成功则返回true否则返回false</returns> public bool ExecuteSqls(List<string> sqlCommands) { if (sqlCommands == null) throw new ArgumentNullException(); if (sqlCommands.Count == 0) throw new ArgumentOutOfRangeException(); if(this.cmd == null) GetCommand(null); SqlTransaction tran = null; try { OpenConn(); tran = this.conn.BeginTransaction(); this.cmd.Transaction = tran; foreach (string sql in sqlCommands) { if (ExecuteNonQuery(sql) == 0) { tran.Rollback(); return false; } } } catch { if (tran != null) tran.Rollback(); throw; } tran.Commit(); return true; } public virtual void Dispose() { if (this.reader != null) { reader.Dispose(); this.reader = null; } if (this.cmd != null) { this.cmd.Dispose(); this.cmd = null; } if (this.conn != null) { this.conn.Dispose(); conn = null; } } protected void OpenConn() { try { if (this.conn.State != ConnectionState.Open) conn.Open(); } catch (SqlException e) { throw e; } } /// <summary> /// 关闭连接 /// </summary> public void CloseConn() { if (this.conn != null && this.conn.State == ConnectionState.Open) this.conn.Close(); } /// <summary> /// 检查Sql语句是否合法 /// </summary> /// <param name="sqlStr">Sql语句</param> protected virtual void CheckArgs(string sqlStr) { if (sqlStr == null) throw new ArgumentNullException(); if (sqlStr.Length == 0) throw new ArgumentOutOfRangeException(); } }} |
以上是关于C# DBHelper 第二版的主要内容，如果未能解决你的问题，请参考以下文章
C# 如何跨线程对Window窗体控件进行安全访问 (第二版)?