关于 writeToFile 读写文件:当字典中键值对以 Model(例如:studentModel)为值时发现 Dictionary 调用 writeToFile 方法无法生成 plist 文件,经过多次测试发现, 调用 writeToFile 方法时 Dictionary 中不能包含 model 对象,针对这一现象,对 model 数据进行处理转化为 Dictionary ,就可以存储为 plist 文件.当读取 plist 文件时再将 Dictionary 转化为 Model.

下面是以 studentModel 为例实现代码:

studentModel 包含三个属性:name,passWord,sex

1 @PRoperty (nonatomic , copy)NSString *name;
2 @property (nonatomic , copy)NSString *passWord;
3 @property (nonatomic , copy)NSString *sex;

为studentModel 添加以实例方法,完成将 Model 对象转为  Dictionary

1 - (NSMutableDictionary *)changeModelToDic{
2     NSMutableDictionary *dic = [[NSMutableDictionary alloc]init];
3     [dic setObject:self.name forKey:@"name"];
4     [dic setObject:self.passWord forKey:@"passWord"];
5     [dic setObject:self.sex forKey:@"sex"];
6     return dic;
7 }

为studentModel 添加类方法.完成将 Dictionary 转化为 Model 对象

1 + (Student*)changDicToStudent:(NSMutableDictionary *)dic{
2     Student *stu = [[Student alloc]init];
3     stu.name = [dic objectForKey:@"name"];
4     stu.passWord = [dic objectForKey:@"passWord"];
5     stu.sex = [dic objectForKey:@"sex"];
6     return stu;
7 }