fmdb +单例

http://www.jianshu.com/p/c7be4535ed87

iOS开发之FMDB的简单使用(单例全局)

 

作者 朱晓晓的技术博客 关注

2016.08.06 10:54 字数 1049 阅读 80评论 0喜欢 0

fmdb是基于sqlite3基础上进行封装,概念性的东西不多说,本demo采用的是队列方式,可以保证线程安全

demo演示

//主要代码:事务回滚,有兴趣的朋友可以自行添加@implementation DBObject+(instancetype)sharedInstance{    static DBObject *sql = nil;    static dispatch_once_t onceToken;    dispatch_once(&onceToken, ^{        sql = [[DBObject alloc]init];    });    return sql;}/** *  初始化字典 * *  @return <#return value description#> */-(NSMutableDictionary *)params{    if (!_params) {        _params = [NSMutableDictionary dictionary];    }    return _params;}/** *  初始化数组(查找全部) * *  @return <#return value description#> */-(NSMutableArray *)Array{    if (!_Array) {        _Array = [NSMutableArray array];    }    return _Array;}/** *  新建数据库+新建表 */-(void)addDatabaseAndTableMethod{    NSString *cachePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)firstObject];    //拼接文件名    NSString *filePath = [cachePath stringByAppendingString:@"note.sqlite"];    NSLog(@"数据库路径:%@",filePath);    //创建数据库,并加入到队列中,此时已经默认打开了数据库,无须手动打开,只需要从队列中去除数据库即可    self.queue = [FMDatabaseQueue databaseQueueWithPath:filePath];    //取出数据库,这里的db就是数据库,在数据库中建表    [self.queue inDatabase:^(FMDatabase *db) {        BOOL createTable = [db executeUpdate:@"create table if not exists t_note (id integer primary key autoincrement,title text,name text,password text)"];        if (createTable) {            NSLog(@"创建表成功");        }        else{            NSLog(@"创建表失败");        }    }];}/** *  新增 */-(void)insetTitle:(NSString *)title WithName:(NSString *)name  WithPassWord:(NSString *)password{    [self.queue inDatabase:^(FMDatabase *db) {        BOOL flag = [db executeUpdate:@"insert into t_note (title,name,password) values (?,?,?)",title,name,password];        if (flag) {            NSLog(@"新增数据成功");        }        else{            NSLog(@"新增数据失败");        }    }];}/** *  删除 */-(void)deleteWithTitle:(NSString *)title{    [self.queue inDatabase:^(FMDatabase *db) {        BOOL flag = [db executeUpdate:@"delete from t_note where title = ?",title];        if (flag) {            NSLog(@"删除数据成功");        }        else{            NSLog(@"删除数据失败");        }    }];}/** *  更新数据 */-(void)updateWithNewName:(NSString *)newName WithTitle:(NSString *)title{    [self.queue inDatabase:^(FMDatabase *db) {        BOOL flag = [db executeUpdate:@"update t_note set name = ? where title = ?",newName,title];        if (flag) {            NSLog(@"更新数据成功");        }        else{            NSLog(@"更新数据失败");        }    }];}/** *  条件查询数据 */-(void)selectWithTitle:(NSString *)title{    [self.queue inDatabase:^(FMDatabase *db) {        //获取结果集,返回参数就是查询结果        FMResultSet *rs = [db executeQuery:@"select *from t_note where title = ?",title];        while ([rs next]) {            self.title = [rs stringForColumn:@"title"];            self.name = [rs stringForColumn:@"name"];            self.password = [rs stringForColumn:@"password"];            NSLog(@"平台:%@---用户名:%@----密码:%@",self.title,self.name,self.password);            //先将数据存放到字典            NSMutableDictionary *dic = [NSMutableDictionary dictionary];            [dic setObject:self.title forKey:@"dictTitle"];            [dic setObject:self.name forKey:@"dictName"];            [dic setObject:self.password forKey:@"dictPwd"];            //然后将字典存放到数组            [self.Array addObject:dic];        }    }];}/** *  查询所有数据 * */-(void)selectAllMethod{    //每次进来查询的时候,先清除上次缓存数据    [self.Array removeAllObjects];    [self.queue inDatabase:^(FMDatabase *db) {        //获取结果集,返回参数就是查询结果        FMResultSet *rs = [db executeQuery:@"select *from t_note"];        while ([rs next]) {            self.title = [rs stringForColumn:@"title"];            self.name = [rs stringForColumn:@"name"];            self.password = [rs stringForColumn:@"password"];            NSLog(@"平台:%@---用户名:%@----密码:%@",self.title,self.name,self.password);            //先将数据存放到字典            NSMutableDictionary *dic = [NSMutableDictionary dictionary];            [dic setObject:self.title forKey:@"dictTitle"];            [dic setObject:self.name forKey:@"dictName"];            [dic setObject:self.password forKey:@"dictPwd"];             //然后将字典存放到数组            [self.Array addObject:dic];        }        NSLog(@"存放的数组:%@==%ld",self.Array,self.Array.count);        [[NSUserDefaults standardUserDefaults]setObject:self.Array forKey:@"Arry"];        [[NSUserDefaults standardUserDefaults]synchronize];    }];}/** *  事务回滚写法1: (如果要保证多个操作同时成功或者同时失败，用事务，即把多个操作放在同一个事务中。) */-(void)updateFailure:(id)sender{    [self.queue inDatabase:^(FMDatabase *db) {        [db beginTransaction];        [db executeUpdate:@"update t_note set name = 'jack' where password = ?",@"12"];        [db executeUpdate:@"update t_note set name = 'tony' where password = ?",@"13"];        //发现情况不对,主动回滚用下面语句.否则是根据commit结果,如成功就成功，如不成功才回滚        [db rollback];        [db executeUpdate:@"update t_note set name = '回滚' where password = ?",@"13"];        [db commit];    }];}/** *  事务回滚写法2:(直接利用队列进行事务操作,队列中的打开、关闭、回滚事务等都已经被封装好了) */-(void)updateFailure02:(id)sender{    [self.queue inDatabase:^(FMDatabase *db) {        [self.queue inTransaction:^(FMDatabase *db, BOOL *rollback) {            [db executeUpdate:@"update t_note set name = 'jack' where password = ?",@"12"];            [db executeUpdate:@"update t_note set name = 'tony' where password = ?",@"13"];            //发现情况不对,主动回滚用下面语句            *rollback = YES;            [db executeUpdate:@"update t_note set name = '回滚' where password = ?",@"13"];        }];    }];}/** *  回滚的原生代码: [db executeUpdate:@"BEGIN TRANSACTION"]; [db executeUpdate:@"ROLLBACK TRANSACTION"]; [db executeUpdate:@"COMMIT TRANSACTION"]; */

demo链接:https://github.com/OwenJoe/FMDB.git