iOS -- 对象归档(将对象存入文件中)

Posted 2020-06-19

// 定义一个对象
Person *p = [[Person alloc] init];
p.name = @"jack";
p.age = 20;
p.height = 180.0;
p.address = @"American";
// 文件存放路径
NSString *path = @"/Users/lianfu/Desktop/one.data";
// 将对象存档
[NSKeyedArchiver archiveRootObject:p toFile:path];

// 读取文件的路径
NSString *path = @"/users/lianfu/Desktop/one.data";
// 将文件中的对象读取出来
Person *p2 = [NSKeyedUnarchiver unarchiveObjectWithFile:path];
NSLog(@"%@, %@, %d, %f", p2.name, p2.address, p2.age, p2.height);

// Person对象需要实现两个方法(且ViewController要遵循协议<NSCoding>)
- (void)encodeWithCoder:(NSCoder *)aCoder{
[aCoder encodeObject:_name forKey:@"name"];
[aCoder encodeInt:_age forKey:@"age"];
[aCoder encodeObject:_address forKey:@"address"];
[aCoder encodeFloat:_height forKey:@"height"];
}
- (id)initWithCoder:(NSCoder *)aDecoder{
if(self = [super init]){
_name = [aDecoder decodeObjectForKey:@"name"];
_age = [aDecoder decodeIntForKey:@"age"];
_height = [aDecoder decodeFloatForKey:@"height"];
_address = [aDecoder decodeObjectForKey:@"address"];
}
return self;
}