How to Save array of custom class in NSUserDefaults ?

Lets say we have an array sampleArray which stores some objects of class called "MyClass"

       sampleArray=[[NSMutableArray alloc]init];

    

    

    MyClass *obj1=[[MyClass alloc]init];

    obj1.name=@"Reetu";

    obj1.sex=@"F";

    obj1.income=@"12";

    obj1.city=@"GUN";

    obj1.mothername=@"ReetuSr.";

    obj1.ethnicity=@"Asian";

    obj1.fathername=@"ReetuDad";

    obj1.countOpen=1;

    [sampleArray addObject:obj1];

    

    MyClass *obj2=[[MyClass alloc]init];

    obj2.name=@"Pinku";

    obj2.sex=@"M";

    obj2.income=@"1223";

    obj2.city=@"ASC";

    obj2.mothername=@"PinkuSr.";

    obj2.ethnicity=@"American";

    obj2.fathername=@"PinkuDad";

    obj2.countOpen=2;

    [sampleArray addObject:obj2];

    

    MyClass *obj3=[[MyClass alloc]init];

    obj3.name=@"Mike";

    obj3.sex=@"M";

    obj3.income=@"125";

    obj3.city=@"PENN";

    obj3.mothername=@"Fred.";

    obj3.ethnicity=@"Caucasian";

    obj3.fathername=@"Fred";

    obj3.countOpen=6;

    [sampleArray addObject:obj3];

Now you want to save this array called sampleArray in NSUserDefault. You will have to use following code.

       NSUserDefaults *userDefault=[NSUserDefaults standardUserDefaults];

    NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:sampleArray];

    [userDefault setObject:myEncodedObject forKey:[NSString stringWithFormat:@"sample"]];

    

As you can see, you will have to use NSKeyedArchiver. you can't use straightforward setObject here otherwise you will get warning like:

-[NSUserDefaults setObject:forKey:]: Attempt to insert non-property value '' of class 'MyClass'.




Later on, when you want to fetch your array from NSUserDefault, you can write following code. Remember it will return non-mutable array.

       //Lets decode it now

    NSData *myDecodedObject = [userDefault objectForKey: [NSString stringWithFormat:@"sample"]];

    NSArray *decodedArray =[NSKeyedUnarchiver unarchiveObjectWithData: myDecodedObject];

    

    

    //Print the array received from User's Default 

    for (MyClass *item in decodedArray) {

        NSLog(@"name=%@",item.name);

        NSLog(@"sex=%@",item.sex);

        NSLog(@"income=%@",item.income);

        NSLog(@"city=%@",item.city);

        NSLog(@"-----------");

    }

    

Well. Last thing, don't forget to add following encode and decode method in your MyClass.

- (void)encodeWithCoder:(NSCoder *)encoder

{

    

    //Encode properties, other class variables, etc

    [encoder encodeObject:self.name forKey:@"name"];

    [encoder encodeObject:self.sex forKey:@"sex"];

    [encoder encodeObject:self.income forKey:@"income"];

    [encoder encodeObject:self.city forKey:@"city"];

    [encoder encodeObject:self.mothername forKey:@"mothername"];

    [encoder encodeObject:self.ethnicity forKey:@"ethnicity"];

    [encoder encodeObject:self.fathername forKey:@"fathername"];    

    [encoder encodeObject:[NSNumber numberWithInt:self.countOpen] forKey:@"destinationCode"];

    

}

- (id)initWithCoder:(NSCoder *)decoder

{

    self = [super init];

    if( self != nil )

    {

        self.name = [decoder decodeObjectForKey:@"name"];

        self.sex = [decoder decodeObjectForKey:@"sex"];

        self.income = [decoder decodeObjectForKey:@"income"];

        self.city = [decoder decodeObjectForKey:@"city"];

        self.mothername = [decoder decodeObjectForKey:@"mothername"];

        self.ethnicity = [decoder decodeObjectForKey:@"ethnicity"];

        self.fathername = [decoder decodeObjectForKey:@"fathername"];

        self.countOpen = [[decoder decodeObjectForKey:@"countOpen"] intValue];

        

    }

    return self;

}

where MyClass has declaration as following

@interface MyClass : NSObject {

    

    NSString *name;

NSString *sex;

NSString *income;

NSString *city;

NSString *mothername;

NSString *ethnicity;

NSString *fathername;

    int countOpen;

}

I have created a sample code for those who still need some clarification. Hope this helps.

Download the Sample Code.