归档与解档

 

 //属性列表的方式，只能存系统定义的类型

    NSArray *array1 = [NSArray arrayWithContentsOfFile:@"/Users/apple/Desktop/test.plist"];

    NSLog(@"%@", array1);

 

    //1. 只能存系统定义的类型

    //2. 不能存太多数据或者是大数据

    NSUserDefaults *userDefault = [NSUserDefaults standardUserDefaults];//单（实）例类

    [userDefault setInteger:2340 forKey:@"age"];

//

    NSInteger age = [userDefault integerForKey:@"age"];

    NSLog(@"%d", age);

    

    NSString *str = @"123abc";

    

    NSData *data = [str dataUsingEncoding:NSUTF8StringEncoding];

    NSLog(@"%@", data);

    

    data = [NSData dataWithContentsOfFile:@"/Users/apple/Desktop/a.out"];

    NSLog(@"%@", data);

    

    NSMutableData *mData = [NSMutableData data];

    [mData appendData:data];

    [mData appendData:data];

    

    [mData writeToFile:@"/Users/apple/Desktop/b.out" atomically:YES];

    

    NSURL *url = [NSURL URLWithString:@"http://sqlite.org/images/foreignlogos/nokia.gif"];

    NSData *nokia = [NSData dataWithContentsOfURL:url];

    [nokia writeToFile:@"/Users/apple/Desktop/nokia.gif" atomically:YES];

}

 

    NSString *str = @"abc";//把abc存入str

    [NSKeyedArchiver archiveRootObject:str toFile:@"/Users/apple/Desktop/test.plist"];//归档

   NSString *str1 = [NSKeyedUnarchiver unarchiveObjectWithFile:@"/Users/apple/Desktop/test.plist"]; //解档

    NSLog(@"%@", str1);

    

    

    Student *stu = [[Student alloc] init];   //自定的类需要实现协议

    stu.name = @"Zhangsan";

    stu.age = 30;

    

//@protocol NSCoding         //自定义的类归档解档需要实现此协议

- (void)encodeWithCoder:(NSCoder *)aCoder;

- (id)initWithCoder:(NSCoder *)aDecoder;//

 

    

    [NSKeyedArchiver archiveRootObject:stu toFile:@"/Users/apple/Desktop/student.plist"];

                                     

    Student *stu1 = [NSKeyedUnarchiver unarchiveObjectWithFile:@"/Users/apple/Desktop/student.plist"];

    NSLog(@"%p, %p", stu, stu1);

    NSLog(@"%@:%d, %@:%d", stu.name, stu.age, stu1.name, stu1.age);

    //stu->path->stu1

 

 

    NSData *stuData = [NSKeyedArchiver archivedDataWithRootObject:stu];//把数据存入NSData

    [stuData writeToFile:@"/Users/apple/Desktop/stu.plist" atomically:YES];//归档

    

    NSData *stuData2 = [NSData dataWithContentsOfFile:@"/Users/apple/Desktop/stu.plist"];

    Student *stu3 = [NSKeyedUnarchiver unarchiveObjectWithData:stuData2];//解档

    NSLog(@"%@:%d---%@:%d", stu.name, stu.age, stu3.name, stu3.age);

    // stu->stuData->path->stuData2->stu3

 

    NSUserDefaults *userDefault = [NSUserDefaults standardUserDefaults];//另外一种方式取值

    [userDefault setObject:stuData forKey:@"xxxx"];//xxxx就等同于stuData

    NSData *stuData3 = [userDefault objectForKey:@"xxxx"];        //中间通过data多一步转换

    

    Student *stu4 = [NSKeyedUnarchiver unarchiveObjectWithData:stuData3];

    NSLog(@"%@:%d", stu4.name, stu4.age);

 

协议的实现如下

- (void)encodeWithCoder:(NSCoder *)aCoder

{

    [aCoder encodeObject:_name forKey:kNameKey];

    [aCoder encodeInteger:_age forKey:kAgeKey];

    [aCoder encodeObject:_dog forKey:kDogKey];

}

 

- (id)initWithCoder:(NSCoder *)aDecoder

{

    self = [super init];

    if (self) {

        self.name = [aDecoder decodeObjectForKey:kNameKey];

        self.age = [aDecoder decodeIntegerForKey:kAgeKey];

        self.dog = [aDecoder decodeObjectForKey:kDogKey];

    }

 

转载于:https://www.cnblogs.com/niang123/p/3883649.html