SQLite3
使用
1 //******************** 5.3 SQLite3存储和读取数据
2 func use_SQLite3()
3 {
4 //声明一个Documents下的路径
5 var dbPath = NSHomeDirectory() + "/Documents/SwiftClassDB.sqlite"
6
7 //判断数据库文件是否存在
8 if !NSFileManager.defaultManager().fileExistsAtPath(dbPath)
9 {
10 //获取安装包内数据库路径
11 var bundleDBPath:String? = NSBundle.mainBundle().pathForResource("SwiftClassDB", ofType: "sqlite")
12
13 //将安装包内数据库拷贝到Documents目录下
14 NSFileManager.defaultManager().copyItemAtPath(bundleDBPath!, toPath: dbPath, error: nil)
15 }
16
17 //打开数据库
18 let dbOperation = DatabaseOperations(dbPath: dbPath)
19
20 //添加一张表
21 dbOperation.createTable();
22
23 //插入一条信息， 通过Person对象来传值
24 let person:Person = Person(name: "刘明洋", pwd: "liumingyang", email: "[email protected]", age: 30)
25
26 dbOperation.addUser(person)
27
28 //查询
29 let personArray:[Person] = dbOperation.readAllUsers()
30 println("共搜索到：\(personArray.count) 条数据" )
31
32
33 //更新
34 dbOperation.updateUser("刘明洋", toName: "刘蕙通")
35
36
37 //删除
38 dbOperation.deleteUser("刘蕙通")
39
40 //关闭数据库
41 dbOperation.colseDb()
42
43
44
45 }
46
47
48 //******************** 5.4 Core Data
49 func use_CoreData()
50 {
51 //参见工程 LMYCoreData
52 }
数据操作
1 class DatabaseOperations {
2
3
4 //不透明指针，对应C语言里面的void *，这里指sqlite3指针
5 private var db:COpaquePointer = nil
6
7
8 //初始化方法打开数据库
9 required init(dbPath:String)
10 {
11 println("db path:" + dbPath)
12
13 //String类的路径，转换成cString
14 let cpath = dbPath.cStringUsingEncoding(NSUTF8StringEncoding)
15
16 //打开数据库
17 let error = sqlite3_open(cpath!, &db)
18
19 //数据库打开失败处理
20 if error != SQLITE_OK {
21 sqlite3_close(db)
22 }
23 }
24
25
26 deinit{
27 self.colseDb()
28 }
29
30
31 //关闭数据库
32 func colseDb(){
33
34 sqlite3_close(db)
35 }
36
37
38
39 //代码创建表
40 func createTable() -> Bool{
41
42 //sql语句
43 var sql = "CREATE TABLE UserTable(id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, username TEXT NOT NULL, password TEXT NOT NULL, email TEXT, age INTEGER)"
44
45 //执行sql语句
46 var execResult = sqlite3_exec(db, sql.cStringUsingEncoding(NSUTF8StringEncoding)!, nil, nil, nil);
47
48 //判断是否执行成功
49 if (execResult != SQLITE_OK) {
50 return false
51 }
52
53 return true
54 }
55
56 //插入一条信息
57 func addUser(user: Person) -> Bool
58 {
59 //sql语句
60 var sql = "INSERT INTO UserTable (username, password, email, age) VALUES (?, ?, ?, ?);";
61 //sql语句转换成cString类型
62
63 var cSql = sql.cStringUsingEncoding(NSUTF8StringEncoding)
64
65 //sqlite3_stmt 指针
66 var stmt:COpaquePointer = nil
67
68
69 //1.编译sql
70 let prepare_result = sqlite3_prepare_v2(self.db, cSql!, -1, &stmt, nil)
71
72 //判断如果失败，获取失败信息
73 if prepare_result != SQLITE_OK {
74 sqlite3_finalize(stmt)
75 if let error = String.fromCString(sqlite3_errmsg(self.db)) {
76 let msg = "SQLiteDB - failed to prepare SQL: \(sql), Error: \(error)"
77 println(msg)
78 self.alert(msg)
79 }
80 return false
81 }
82
83
84 let intTran = UnsafeMutablePointer<Int>(bitPattern: -1)
85 let tranPointer = COpaquePointer(intTran)
86 let transient = CFunctionPointer<((UnsafeMutablePointer<()>) -> Void)>(tranPointer)
87
88 //2.bind 绑定参数
89 //第2个参数：索引从1开始
90 //最后一个参数为函数指针
91 sqlite3_bind_text(stmt, 1, user.name!.cStringUsingEncoding(NSUTF8StringEncoding)!, -1, transient);
92 sqlite3_bind_text(stmt, 2, user.password!.cStringUsingEncoding(NSUTF8StringEncoding)!, -1, transient);
93 sqlite3_bind_text(stmt, 3, user.email!.cStringUsingEncoding(NSUTF8StringEncoding)!, -1, transient);
94 sqlite3_bind_int(stmt, 4, CInt(user.age!));
95
96
97 //3.step执行
98 var step_result = sqlite3_step(stmt)
99
100 //判断执行结果，如果失败，获取失败信息
101 if step_result != SQLITE_OK && step_result != SQLITE_DONE {
102 sqlite3_finalize(stmt)
103 if let err = String.fromCString(sqlite3_errmsg(self.db)) {
104 let msg = "SQLiteDB - failed to execute SQL: \(sql), Error: \(err)"
105 println(msg)
106 self.alert(msg)
107 }
108 return false
109 }
110
111 //4.finalize
112 sqlite3_finalize(stmt);
113
114 return true
115 }
116
117 //查询
118 func readAllUsers() -> [Person]{
119
120 //声明一个Person对象数组（查询的信息会添加到该数组）
121 var usersArr = [Person]()
122
123 //查询sql语句
124 var sql = "SELECT * FROM UserTable;";
125
126 //sqlite3_stmt 指针
127 var stmt:COpaquePointer = nil
128 var cSql = sql.cStringUsingEncoding(NSUTF8StringEncoding)
129
130 //1.编译sql
131 let prepare_result = sqlite3_prepare_v2(self.db, cSql!, -1, &stmt, nil)
132 if prepare_result != SQLITE_OK {
133 sqlite3_finalize(stmt)
134 if let error = String.fromCString(sqlite3_errmsg(self.db)) {
135 let msg = "SQLiteDB - failed to prepare SQL: \(sql), Error: \(error)"
136 println(msg)
137 self.alert(msg)
138 }
139 return usersArr
140 }
141
142 //2.step
143 while (sqlite3_step(stmt) == SQLITE_ROW) {
144 var user = Person()
145
146 //循环 从数据库获取数据，添加到数组中
147 let cName = UnsafePointer<CChar>(sqlite3_column_text(stmt, 0))
148 let cPwd = UnsafePointer<CChar>(sqlite3_column_text(stmt, 1))
149 let cEmail = UnsafePointer<CChar>(sqlite3_column_text(stmt, 2))
150 let cAge = sqlite3_column_int(stmt, 3)
151
152 user.name = String.fromCString(cName)
153 user.password = String.fromCString(cPwd)
154 user.email = String.fromCString(cEmail)
155 user.age = Int(cAge)
156
157 usersArr += [user]
158 }
159
160 //3.finalize
161 sqlite3_finalize(stmt);
162
163 return usersArr
164 }
165
166 //更新一条信息
167 func updateUser(name: String , toName:String) -> Bool
168 {
169 //更新sql语句
170 var sql = "update UserTable set username = ‘\(toName)‘ where username = ‘\(name)‘";
171
172 //sqlite3_stmt 指针
173 var stmt:COpaquePointer = nil
174 var cSql = sql.cStringUsingEncoding(NSUTF8StringEncoding)
175
176 //1.编译sql
177 let prepare_result = sqlite3_prepare_v2(self.db, cSql!, -1, &stmt, nil)
178
179 //判断如果失败，获取失败信息
180 if prepare_result != SQLITE_OK {
181 sqlite3_finalize(stmt)
182 if let error = String.fromCString(sqlite3_errmsg(self.db)) {
183 let msg = "SQLiteDB - failed to prepare SQL: \(sql), Error: \(error)"
184 println(msg)
185 self.alert(msg)
186 }
187 return false
188 }
189
190 //3.step执行
191 var step_result = sqlite3_step(stmt)
192
193 //判断执行结果，如果失败，获取失败信息
194 if step_result != SQLITE_OK && step_result != SQLITE_DONE {
195 sqlite3_finalize(stmt)
196 if let err = String.fromCString(sqlite3_errmsg(self.db)) {
197 let msg = "SQLiteDB - failed to execute SQL: \(sql), Error: \(err)"
198 println(msg)
199 self.alert(msg)
200 }
201 return false
202 }
203
204 //4.finalize
205 sqlite3_finalize(stmt);
206
207 return true
208 }
209
210
211 //删除一条信息
212 func deleteUser(username: String) -> Bool
213 {
214 //删除sql语句
215 var sql = "delete from UserTable where username = ‘\(username)‘";
216
217 //sqlite3_stmt 指针
218 var stmt:COpaquePointer = nil
219 var cSql = sql.cStringUsingEncoding(NSUTF8StringEncoding)
220
221 //1.编译sql
222 let prepare_result = sqlite3_prepare_v2(self.db, cSql!, -1, &stmt, nil)
223
224 //判断如果失败，获取失败信息
225 if prepare_result != SQLITE_OK {
226 sqlite3_finalize(stmt)
227 if let error = String.fromCString(sqlite3_errmsg(self.db)) {
228 let msg = "SQLiteDB - failed to prepare SQL: \(sql), Error: \(error)"
229 println(msg)
230 self.alert(msg)
231 }
232 return false
233 }
234
235 //3.step执行
236 var step_result = sqlite3_step(stmt)
237
238 //判断执行结果，如果失败，获取失败信息
239 if step_result != SQLITE_OK && step_result != SQLITE_DONE {
240 sqlite3_finalize(stmt)
241 if let err = String.fromCString(sqlite3_errmsg(self.db)) {
242 let msg = "SQLiteDB - failed to execute SQL: \(sql), Error: \(err)"
243 println(msg)
244 self.alert(msg)
245 }
246 return false
247 }
248
249 //4.finalize
250 sqlite3_finalize(stmt);
251
252 return true
253 }
254
255
256
257
258 //定义一个报警器
259 func alert(msg:String) {
260 dispatch_async(dispatch_get_main_queue()) {
261 let alert = UIAlertView(title: "SQLiteDB", message:msg, delegate: nil, cancelButtonTitle: "OK")
262 alert.show()
263 }
264 }
265 }
时间： 2024-08-26 03:48:16