数据库（FMDB）-城市数据的缓存
这是终的效果图
创建并打开数据库 #pragma mark -- 数据库处理 //创建并打开数据库 - (void)openSqlData{ NSString *doc = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory， NSUserDomainMask， YES) lastObject]; NSLog(@"sql路径===%@"，doc); NSString *fileName = [doc stringByAppendingPathComponent:@"city.sqlite"]; FMDatabaseQueue *dbQueue = [FMDatabaseQueue databaseQueueWithPath:fileName]; [dbQueue inDatabase:^(FMDatabase *db) { BOOL result = [db executeUpdate:@"create table if not exists t_city (id integer primary key autoincrement，pid integer not null，name text not null，pinyin text not null，firstletter text not null，hotcity integer not null);"]; if (result) { NSLog(@"打开成功"); }else{ NSLog(@"打开失败"); } }]; self.dbQueue = dbQueue; } 传入模型数组，向数据库中插入数据 //根据模型数组插入数据库中 - (void)insertData:(CityModel *)cityModel{ DefineWeakSelf; //删除数据库数据 __block NSString *insertStr = @""; [self.dbQueue inDatabase:^(FMDatabase *db) { NSString *deleteStr = [NSString stringWithFormat:@"delete from t_city"]; if (![db executeUpdate:deleteStr]) { NSLog(@"删除数据库记录失败。。。"); } //开启事务 [db beginTransaction]; BOOL isRollBack = NO; @try { [cityModel.positionList enumerateObjectsUsingBlock:^(CityEntity *entity， NSUInteger idx， BOOL * _Nonnull stop) { insertStr =[NSString stringWithFormat:@"insert into t_city(pid，name，pinyin，firstletter，hotcity) values ('%@'，'%@'，'%@'，'%@'，'%@');"，@(entity.pid)，entity.name，entity.pinyin，entity.firstLetter，@(0)]; if (![db executeUpdate:insertStr]) { NSLog(@"插入数据失败"); } }]; } @catch (NSException *exception) { //插入出错，自动回滚 isRollBack = YES; [db rollback]; } @finally { //提交事务 if (!isRollBack) { [db commit]; } } }]; } 查询数据，并存到字典中 //查询并处理数据 - (void)queryData{ DefineWeakSelf; [self.dbQueue inDatabase:^(FMDatabase *db) { NSString *firstStr = @"a"; //执行查询语句 并以升序排列 FMResultSet *resultSet = [db executeQuery:@"select * from t_city order by firstletter asc"]; //遍历结果 while ([resultSet next]) { NSString *title = [resultSet stringForColumn:@"firstletter"]; NSString *name = [resultSet stringForColumn:@"name"]; NSInteger hotcity = [resultSet intForColumn:@"hotcity"]; if (hotcity == 1) { [wSelf.hotcityArray addObject:name]; } if ([title isEqualToString:firstStr]) { [wSelf.cityArray addObject:name]; }else{ [wSelf.titleArray addObject:[firstStr uppercaseString]]; wSelf.cityDictionary[firstStr] = wSelf.cityArray; firstStr = title; wSelf.cityArray = [NSMutableArray array]; [wSelf.cityArray addObject:name]; } } if (![firstStr isEqualToString:@"a"]) { [wSelf.titleArray addObject:[firstStr uppercaseString]]; wSelf.cityDictionary[firstStr] = wSelf.cityArray; } }]; [self.cityChooseTableView reloadData]; } 模糊搜索 //模糊查询 - (void)queryByString:(NSString *)queryStr{ DefineWeakSelf; _isSearch = YES; _searchArr = [NSMutableArray array]; [self.dbQueue inDatabase:^(FMDatabase *db) { //根据城市拼音或名字 模糊搜索 NSString *sql = [NSString stringWithFormat:@"select * from t_city where pinyin like '%@%%' or name like '%@%%';"，[queryStr lowercaseString]，queryStr]; FMResultSet *resultSet = [db executeQuery:sql]; while ([resultSet next]) { NSLog(@"%@"，[resultSet stringForColumn:@"name"]); [wSelf.searchArr addObject:[resultSet stringForColumn:@"name"]]; } [wSelf.cityChooseTableView reloadData]; }]; }
