1、NSData归档多个对象
一、之前我写的学习笔记都是归档一个对象，如果需要归档多个对象我们需要借助NSData
二、步骤
1）、NSMutableData作为参数，构建 NSKeyedArchiver对象
2）、调用NSKeyedArchiver的encodeXXX
3)、调用NSKeyedArchiver的finishEncoding方法
4)、NSMutableData保存到文件
2、归档对象实现深复制
我们知道深复制就是复制对象和原始对象没有任何公用的部分，修改复制对象的值不会对原始对象产生影响。
步骤
1）、NSKeyedArchiver的archivedDataWithRootObject
2）、NSKeyedUnarchiver的unarchiveObjectWithData
3、实现Demo
IApple.h
#import <Foundation/Foundation.h> #ifndef IApple_h #define IApple_h @interface IApple : NSObject <NSCoding> @property (nonatomic, copy) NSString *color; @property (nonatomic, assign) double weight; @property (nonatomic, assign) int size; -(id)initWithColor:(NSString *) color weight:(double) weight size:(int) size; @end #endif /* IApple_h */
IApple.m
#import "IApple.h" #import <Foundation/Foundation.h> @implementation IApple @synthesize color = _color; @synthesize weight = _weight; @synthesize size = _size; -(id)initWithColor:(NSString *) color weight:(double) weight size:(int) size { if (self = [super init]) { self.color = color; self.weight = weight; self.size = size; } return self; } -(NSString *)description { return [NSString stringWithFormat:@"<IApple [color = %@, weight = %g, _size = %d]>", self.color, self.weight, self.size]; } -(void)encodeWithCoder:(NSCoder *)aCoder { [aCoder encodeObject:_color forKey:@"color"]; [aCoder encodeDouble:_weight forKey:@"weight"]; [aCoder encodeInt:_size forKey:@"size"]; } -(id) initWithCoder:(NSCoder *)aDecoder { _color = [aDecoder decodeObjectForKey:@"color"]; _weight = [aDecoder decodeDoubleForKey:@"weight"]; _size = [aDecoder decodeIntForKey:@"size"]; return self; } @end
IApple.m
#import "IApple.h" #import <Foundation/Foundation.h> @implementation IApple @synthesize color = _color; @synthesize weight = _weight; @synthesize size = _size; -(id)initWithColor:(NSString *) color weight:(double) weight size:(int) size { if (self = [super init]) { self.color = color; self.weight = weight; self.size = size; } return self; } -(NSString *)description { return [NSString stringWithFormat:@"<IApple [color = %@, weight = %g, _size = %d]>", self.color, self.weight, self.size]; } -(void)encodeWithCoder:(NSCoder *)aCoder { [aCoder encodeObject:_color forKey:@"color"]; [aCoder encodeDouble:_weight forKey:@"weight"]; [aCoder encodeInt:_size forKey:@"size"]; } -(id) initWithCoder:(NSCoder *)aDecoder { _color = [aDecoder decodeObjectForKey:@"color"]; _weight = [aDecoder decodeDoubleForKey:@"weight"]; _size = [aDecoder decodeIntForKey:@"size"]; return self; } @end
main.m
#import "IApple.h" int main(int argc, char * argv[]) { @autoreleasepool { NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:80], @"java", [NSNumber numberWithInt:90], @"c", [NSNumber numberWithInt:70], @"oc", [NSNumber numberWithInt:100], @"c++",nil]; NSSet *set = [NSSet setWithObjects:@"java", @"ios", @"c++", @"oc", nil]; IApple *apple = [[IApple alloc] initWithColor:@"red" weight:50 size:20]; NSMutableData *data = [NSMutableData data]; NSKeyedArchiver *arch = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data]; //归档对象 [arch encodeObject:dict forKey:@"dict"]; [arch encodeObject:set forKey:@"set"]; [arch encodeObject:apple forKey:@"apple"]; //结束归档 [arch finishEncoding]; //在document目录下创建一个chenyu.txt空文件 NSArray *docPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *path = [docPaths objectAtIndex:0]; NSLog(@"document path:%@", path); NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *chenyuPath = [path stringByAppendingPathComponent:@"chenyu.txt"]; BOOL isSuccess = [fileManager createFileAtPath:chenyuPath contents:nil attributes:nil]; if (isSuccess) { NSLog(@"make chenyu.txt success"); } else { NSLog(@"make chenyu.txt fail"); } //归档对象到chenyu.txt文件 if([data writeToFile:chenyuPath atomically:YES] == YES) { NSLog(@"归档对象成功"); } else { NSLog(@"归档对象失败"); } //读取归档对象 NSData *readData = [NSData dataWithContentsOfFile:chenyuPath]; NSKeyedUnarchiver *unArch = [[NSKeyedUnarchiver alloc] initForReadingWithData:readData]; NSDictionary *readDict = [unArch decodeObjectForKey:@"dict"]; NSSet *readSet = [unArch decodeObjectForKey:@"set"]; NSSet *readApple = [unArch decodeObjectForKey:@"apple"]; NSLog(@"readDict is:%@", readDict); NSLog(@"readSet is:%@", readSet); NSLog(@"readApple is %@", readApple); //使用归档对戏实现深复制 深复制就是复制对象和本身对象没有任何公用部分，所以修改复制对象的属性不会影响原始对象的属性 NSDictionary *diction = [NSDictionary dictionaryWithObjectsAndKeys:[[IApple alloc] initWithColor:@"red" weight:50 size:20], @"one", [[IApple alloc] initWithColor:@"green" weight:60 size:21], @"two", nil]; //对象归档 NSData *data1 = [NSKeyedArchiver archivedDataWithRootObject:diction]; //回复对象 NSDictionary *dictCopy = [NSKeyedUnarchiver unarchiveObjectWithData:data1]; IApple *app = [dictCopy objectForKey:@"one"]; [app setColor:@"green"]; IApple *app1 = [diction objectForKey:@"one"]; NSLog(@"app1 color is:%@", app1.color); } }
4、运行结果
2018-07-22 19:34:11.258816+0800 cyTest[62704:16613816] document path:*****/3FF9B833-FAF8-4C30-A855-3D40A4EAE8A6/data/Containers/Data/Application/6AD520C9-3A99-45B5-A2F9-4E4D7CA77486/Documents 2018-07-22 19:34:11.269539+0800 cyTest[62704:16613816] make chenyu.txt success 2018-07-22 19:34:11.271898+0800 cyTest[62704:16613816] 归档对象成功 2018-07-22 19:34:11.272976+0800 cyTest[62704:16613816] readDict is:{ c = 90; "c++" = 100; java = 80; oc = 70; } 2018-07-22 19:34:11.273243+0800 cyTest[62704:16613816] readSet is:{( "c++", java, ios, oc )} 2018-07-22 19:34:11.273602+0800 cyTest[62704:16613816] readApple is <IApple [color = red, weight = 50, _size = 20]> 2018-07-22 19:34:11.274150+0800 cyTest[62704:16613816] app1 color is:red
