对象归档

    //保存图片

    //1,NSDocument

    NSString *documentPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;

    NSString *path = [documentPath stringByAppendingString:@"/img.png"];

    //2,创建

    UIImage *image = [UIImage imageNamed:@"1.png"];

    //3,save

    NSData *imgData = UIImagePNGRepresentation(image);//png -> data

    [imgData writeToFile:path atomically:YES];

    NSLog(@"%@",path);

    ///////对象归档

    ////////////////复杂对象

    //1,

    Student *stu = [[Student new] autorelease];

    stu.name = @"name";

    stu.age = 11;

    stu.hobby = @"fff";

    //1,转成nsdata

    NSMutableData *mutableData = [NSMutableData data];

    //2,创建归档工具

    NSKeyedArchiver *archiver = [[[NSKeyedArchiver alloc] initForWritingWithMutableData:mutableData] autorelease];

    //2.3 归档

    [archiver encodeObject:stu forKey:@"stu"];

    //2,4 完成

    [archiver finishEncoding];

    //3,保存文件

    NSString *stuPath = [documentPath stringByAppendingString:@"/student"];

    //3,1写入

    [mutableData writeToFile:stuPath atomically:YES];

    /////4,取出

    NSData *stuData = [NSData dataWithContentsOfFile:stuPath];

    //4,1

    NSKeyedUnarchiver *unarchiver = [[[NSKeyedUnarchiver alloc] initForReadingWithData:stuData] autorelease];

    //4,2 反归档

    Student *resultStu = [unarchiver decodeObjectForKey:@"stu"];

    //4,3 结束

    [unarchiver finishDecoding];

    NSLog(@"%@,%lu,%@",resultStu.name,resultStu.age,resultStu.hobby);

    //、、、、、直接归档

    Student *s1 = [[[Student alloc] init] autorelease];

    s1.name = @"jj";

    s1.hobby = @"oo";

    s1.age = 11;

    //

    NSString *stuPath1 = [documentPath stringByAppendingString:@"/stu1"];

    [NSKeyedArchiver archiveRootObject:s1 toFile:stuPath1];

    //

    Student *s2 = [NSKeyedUnarchiver unarchiveObjectWithFile:stuPath1];

    NSLog(@"%@%@%lu",s2.name,s2.hobby,s2.age);