在iOS中实现SQLite数据库的操作:1.导入框架(libsqlite3.0.tbd) 2.导入头文件<sqlite3.h> 3.实现数据的增删改查
实现简单 SQLite数据库操作 的 demo 具体过程:
1.创建名为 SQLite_Manage 的.h .m 文件,导入头文件 <sqlite3.h>
2.数据库在一个app中只有一个,使用单例模式:(代码如下)
1 + (SQLite_Manager *)sharedManager{
2 static SQLite_Manager *manager = nil;
3 static dispatch_once_t onceToken;
4 dispatch_once(&onceToken, ^{
5 manager = [[SQLite_Manager alloc]init];
6 });
7 return manager;
8 }
3.打开数据库,代码如下:
1 - (void)open{
2 //document路径
3 NSString *docment = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
4 //sqlite 路径
5 NSString *sqlitePath = [docment stringByAppendingPathComponent:@"database.sqlite"];
6 //打开数据库
7 int result = sqlite3_open(sqlitePath.UTF8String, &db);
8 //判断数据库是否打开成功
9 if (result == SQLITE_OK) {
10 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"打开成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
11 [alertView show];
12 }else {
13 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"打开失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
14 [alertView show];
15 }
16 }
4.创建表,代码如下:
1 - (void)creatTable{
2 //sql语句
3 NSString *sqlString = @"create table Person (id integer primary key,name text,age integer)";
4 //执行SQL语句
5 char *error = nil;
6 sqlite3_exec(db, sqlString.UTF8String, nil, nil, &error);
7
8 //判断是否出现了错误
9 if (error == nil){
10 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"创建表成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
11 [alertView show];
12 }else {
13 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"创建表失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
14 [alertView show];
15 }
16 }
5.插入数据,代码如下:
1 - (void)insert{
2 //sql语句
3 NSString *sqlString = @"insert into Person ('name','age') values ('Ager',18)";
4 //执行SQL语句
5 char *error = nil;
6 sqlite3_exec(db, sqlString.UTF8String, nil, nil, &error);
7 //判断是否出现了错误
8 if (error == nil){
9 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"插入数据成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
10 [alertView show];
11 }else {
12 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"插入数据失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
13 [alertView show];
14 }
15
16 }
6.修改数据,代码如下:
1 - (void)update{
2 //sql语句
3 NSString *sqlString = @"update Person set 'name' = 'Arun' where id = 1";
4 //执行sql语句
5 char *error = nil;
6 sqlite3_exec(db, sqlString.UTF8String, nil, nil, &error);
7
8 //判断是否出现了错误
9 if (error == nil){
10 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"数据更新成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
11 [alertView show];
12 }else {
13 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"数据更新失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
14 [alertView show];
15 }
16 }
7.查询数据,代码如下:
1 - (void)select{
2 //sql语句
3 NSString *sqlString = @"select * from Person";
4 //准备sql
5 sqlite3_stmt *stmt = nil;
6 sqlite3_prepare(db, sqlString.UTF8String,-1, &stmt, nil);
7 //单步执行语句
8 while (sqlite3_step(stmt) == SQLITE_ROW) {
9 int ID = sqlite3_column_int(stmt, 0);
10 const unsigned char *name = sqlite3_column_text(stmt, 1);
11 int age = sqlite3_column_int(stmt, 2);
12 NSLog(@"%d,%s,%d",ID,name,age);
13 }
14 sqlite3_finalize(stmt);
15 }
8.删除数据,代码如下:
1 - (void)deleteData{
2 //sql语句
3 NSString *sqlString = @"delete from Person where id = 1";
4 //执行sql语句
5 char *error = nil;
6 sqlite3_exec(db, sqlString.UTF8String, nil, nil, &error);
7 //判断是否出现了错误
8 if (error == nil){
9 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"删除成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
10 [alertView show];
11 }else {
12 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"删除失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
13 [alertView show];
14 }
15 }
9.关闭数据库,代码如下:
1 - (void)close{
2 //关闭数据库
3 int result = sqlite3_close(db);
4 //判断数据库是否关闭成功
5 if (result == SQLITE_OK) {
6 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"关闭成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
7 [alertView show];
8 }else {
9 UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"数据库执行结果" message:@"关闭失败" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定", nil];
10 [alertView show];
11 }
12 }