iOS 使用FMDB进行数据库操作

1、首先要先导入第三方类库FMdatabase。2、获得存放数据库文件的沙盒地址。+(NSString*)databaseFilePath

{NSArray*filePath=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);NSString*documentPath=[filePathobjectAtIndex:0];NSLog(@"%@",filePath);NSString*dbFilePath=[documentPathstringByAppendingPathComponent:@"db.sqlite"];returndbFilePath;}3、创建数据库的操作+(void)creatDatabase{db=[[FMDatabasedatabaseWithPath:[selfdatabaseFilePath]]retain];}4、创建表+(void)creatTable{//先判断数据库是否存在，如果不存在，创建数据库if(!db){[selfcreatDatabase];}//判断数据库是否已经打开，如果没有打开，提示失败if(![dbopen]){NSLog(@"数据库打开失败");return;}//为数据库设置缓存，提高查询效率[dbsetShouldCacheStatements:YES];//判断数据库中是否已经存在这个表，如果不存在则创建该表if(![dbtableExists:@"people"]){[dbexecuteUpdate:@"CREATETABLES people(people_id INTEGER PRIMARY KEY AUTOINCREAMENT, nameTEXT, age INTEGER) "];NSLog(@"创建完成");}}5、增加表数据+(void)insertPeople:(People*)aPeople{if(!db){[selfcreatDatabase];}if(![dbopen]){NSLog(@"数据库打开失败");return;}[dbsetShouldCacheStatements:YES];if(![dbtableExists:@"people"]){[selfcreatTable];}//以上操作与创建表是做的判断逻辑相同//现在表中查询有没有相同的元素，如果有，做修改操作FMResultSet*rs=[dbexecuteQuery:@"select* from people where people_id = ?",[NSStringstringWithFormat:@"%d",aPeople.peopleID]];if([rsnext]){NSLog(@"dddddslsdkien");[dbexecuteUpdate:@"updatepeople set name = ?, age = ? where people_id =1",aPeople.name,[NSStringstringWithFormat:@"%d",aPeople.age]];}//向数据库中插入一条数据else{[dbexecuteUpdate:@"INSERTINTO people (name, age) VALUES(?,?)",aPeople.name,[NSStringstringWithFormat:@"%d",aPeople.age]];}}6、删除数据+(void)deletePeopleByID:(int)ID{if(!db){[selfcreatDatabase];}if(![dbopen]){NSLog(@"数据库打开失败");return;}[dbsetShouldCacheStatements:YES];//判断表中是否有指定的数据， 如果没有则无删除的必要，直接returnif(![dbtableExists:@"people"]){return;}//删除操作[dbexecuteUpdate:@"deletefrom people where people_id = ?", [NSStringstringWithFormat:@"%d",ID]];[dbclose];}7、修改操作与增加操作的步骤一致+(NSArray*)getAllPeople{if(!db){[selfcreatDatabase];}if(![dbopen]){NSLog(@"数据库打开失败");returnnil;}[dbsetShouldCacheStatements:YES];if(![dbtableExists:@"people"]){returnnil;}//定义一个可变数组，用来存放查询的结果，返回给调用者NSMutableArray*peopleArray=[[NSMutableArrayalloc]initWithArray:0];//定义一个结果集，存放查询的数据FMResultSet*rs=[dbexecuteQuery:@"select* from people"];//判断结果集中是否有数据，如果有则取出数据while([rsnext]){People*aPeople=[[Peoplealloc]init];aPeople.peopleID=[rsintForColumn:@"people_id"];aPeople.name=[rsstringForColumn:@"name"];aPeople.age=[rsintForColumn:@"age"];//将查询到的数据放入数组中。[peopleArrayaddObject:aPeople];}return[peopleArrayautorelease];}8、查询+(NSArray*)getAllPeople{if(!db){[selfcreatDatabase];}if(![dbopen]){NSLog(@"数据库打开失败");returnnil;}[dbsetShouldCacheStatements:YES];if(![dbtableExists:@"people"]){returnnil;}//定义一个可变数组，用来存放查询的结果，返回给调用者NSMutableArray*peopleArray=[[NSMutableArrayalloc]initWithArray:0];//定义一个结果集，存放查询的数据FMResultSet*rs=[dbexecuteQuery:@"select* from people"];//判断结果集中是否有数据，如果有则取出数据while([rsnext]){People*aPeople=[[Peoplealloc]init];aPeople.peopleID=[rsintForColumn:@"people_id"];aPeople.name=[rsstringForColumn:@"name"];aPeople.age=[rsintForColumn:@"age"];//将查询到的数据放入数组中。[peopleArrayaddObject:aPeople];}return[peopleArrayautorelease];}