数据持久化-写入plist

需要确定我们想要存入plist的格式,这里我以数组包字典的格式作为例子(格式可以自己选择,放发都是一样的)

写入plist

• 创建内层字典

NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];

• 将想要存入的信息添加到字典中(这里以字符串为例子)

[dictionary setObject:@"24K纯金洋" forKey:@"content"];

• 获取document文件夹的路径

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);    NSString *documentDirectory = [paths objectAtIndex:0];

• 设置plist的路径

NSString *plistPath = [documentDirectory stringByAppendingPathComponent:@"yang.plist"];

• 创建文件管理者

NSFileManager *fileManager = [[NSFileManager alloc] init];

• 写入本地

//查看路径内是否有plist文件//如果没有穿件一个//如果有执行写入操作if (![fileManager fileExistsAtPath:plistPath]) {//如果创建失败,提示用户        if (![fileManager createFileAtPath:plistPath contents:nil attributes:nil]) {            NSAssert(NO, @"Failed to create file");        }else{        //如果成功,写入plist            NSMutableArray *array = [NSMutableArray arrayWithObject:historyDic];            [array writeToFile:plistPath atomically:YES];        }    }else{    //如果路径内有plist文件,先将数组取出,添加新内容,再写入        NSMutableArray *array = [[NSMutableArray alloc] initWithContentsOfFile:plistPath];        [array addObject:historyDic];        [array writeToFile:plistPath atomically:YES];    }

取出plist

其实创建的时候已经有过取出的操作

NSFileManager *fileManager = [NSFileManager defaultManager];    NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);    NSString *documentation = [path objectAtIndex:0];    [fileManager changeCurrentDirectoryPath:[documentation stringByExpandingTildeInPath]];    NSString *historyPlistPath = [documentation stringByAppendingPathComponent:@"history.plist"];    NSMutableArray *array = [[NSMutableArray alloc] initWithContentsOfFile:historyPlistPath];

取出数组候可以对数组操作,一下内容都是基于取出plist的,所以下面的代码取出的部分就直接省略了

删除全部

if (array.count != 0) {        if ([fileManager fileExistsAtPath:historyPlistPath]) {            [array removeAllObjects];            [array writeToFile:historyPlistPath atomically:YES];        }    }

• 额!不够完整,我的项目中先在就用到这几个方法,有时间继续!