什么是归档？什么是解档？
归档：就是把对象序列化，序列化就是把对象写到一个指定的app路径下的文件里，app有三个目录分别是：docments、library、tmp，也叫做对象的持久化，ios开发中一般的持久化不支持自定义对象的持久化，归档解档就可以完成自定义对象的持久化。
实现归档解档的步骤： Step1：要实现对象的归档解档首先继承Coding协议（protocol）
Step2：实现两个方法：encodeWihtCoder: 和 initWithCoder:
runtime实现方法 少写很多的给属性赋值的方法
//归档 - (void)encodeWithCoder:(NSCoder*)aCoder { NSLog(@"归档encodeWithCoder方法调用了"); unsigned int count = 0; Ivar* ivars = class_copyIvarList([self class], &count); for (int i = 0; i < count; i++) { Ivar ivar = ivars[i]； const char* name = ivar_getName(ivar); NSString* key = [NSString stringWithUTF8String:name]; [aCoder encodeObject:[self valueForKey:key] forKey :key]; } free(ivars); } //解档 - (id)initWithCoder:(NSCoder*)aDecoder { NSLog(@"解档initWithCoder方法调用了"); if (self == [super init]) { unsigned int count = 0; Ivar* ivars = class_copyIvarList([self class], &count); for (int i = 0; i < count; i++) { Ivar ivar = ivars[i]; const char* name = ivar_getName(ivar); NSString* key = [NSString stringWithUTF8String:name]; id value = [aDecoder decodeObjectForKey:key];//根据key拿到value [self setValue:value forKey:key];//KVC赋值 } free(ivars); } return self; }使用： 归档
//获取文件目录 NSString* docPatn = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject]; //NSString* homePath = NSTemporaryDirectory(); NSLog(@"docPath = %@",docPatn); NSLog(@"homePath = %@",homePath); NSString* path = [docPatn stringByAppendingPathComponent:@"zht.hank"]; //自定义对象存到文件中 [NSKeyedArchiver archiveRootObject:person toFile:path]; 解档： ZHTPerson* p = [NSKeyedUnarchiver unarchiveObjectWithFile:path]; NSLog(@"name = %@,age = %d",p.name,p.age);