iOS Dev-store uses nscoding archiving and anti-archiving

iOS development in order to store objects can use Nscoding, the object to be stored must experiment nscoding protocol

For example, if we want to store a student object, then the student class must follow the Nscoding protocol and then implement the two methods in Nscoding.

@interface Student : NSObject  <NSCoding>

Then the. m file implements Encodewithcoder: (Save) and Initwithcoder: (read) method, which tells the program how the object should be stored, the properties to be stored, and how to read it!

/** * Called when an object is written to a file * In this method, it is clear which attributes need to be stored */-(void ) Encodewithcoder: (Nscoder *) encoder{[encoder    encodeObject:self.no forkey:@ "no" ];    [Encoder encodeInt:self.age Forkey:@ "age" ]; [Encoder encodeDouble:self.height Forkey:@ "height" ];}  

/** *  从文件中解析对象时会调用 *  在这个方法中说清楚哪些属性需要存储 */- (id)initWithCoder:(NSCoder *)decoder{    if (self = [super init]) {        // 读取文件的内容        self.no = [decoder decodeObjectForKey:@"no"];        self.age = [decoder decodeIntForKey:@"age"];        self.height = [decoder decodeDoubleForKey:@"height"];    }    return self;}

Read and Write methods in the controller.

- (ibaction) Save {//1. New Model ObjectStudent *stu = [[Student alloc] init]; Stu. No= @"42343254"; Stu. Age= -; Stu. Height=1.55;//2. Archiving Model Objects    //2.1. Get full path to documents    NSString*doc = [Nssearchpathfordirectoriesindomains (NSDocumentDirectory, Nsuserdomainmask,YES) Lastobject];//2.2. Get the full path of the file    NSString*path = [Doc stringbyappendingpathcomponent:@"Stu.data"];//2.3. Archive an Object[Nskeyedarchiver archiverootobject:stu Tofile:path];}

Anti-archive (read)

- (IBAction)read {    // 1.获得Documents的全路径    NSStringYES) lastObject];    // 2.获得文件的全路径    NSString *path = [doc stringByAppendingPathComponent:@"stu.data"];    // 3.从文件中读取MJStudent对象    Student *stu = [NSKeyedUnarchiver unarchiveObjectWithFile:path];}

iOS Dev-store uses nscoding archiving and anti-archiving