NSUserDefaults的無法保存的NSMutableDictionary

Question

蔭努力的NSMutableDictionary保存到NSUserDefaults的與此代碼：

NSUserDefaults *def = [NSUserDefaults standardUserDefaults]; 
NSMutableDictionary *repositoryData = [[NSMutableDictionary alloc] init]; 

[repositoryData setObject:personData forKey:@"persondata"]; 

[def setObject:repositoryData forKey:@"kUserRepository"]; 
[def synchronize]; 
[repositoryData removeAllObjects]; 
[repositoryData release]; 

但我得到這個消息：

[NSUserDefaults setObject:forKey:]: Attempt to insert non-property value '{ 
    persondata = "<Person: 0x1ed57e70>"; 
}' of class '__NSDictionaryM'. Note that dictionaries and arrays in property lists must also contain only property values. 

也Person類有NSCoding：

Person.h

@interface Person : NSObject <NSCoding> { 
    NSString *name; 
    NSString *email; 
    NSString *phoneNumber; 
    NSString *gender; 

    int age; 
} 

@property (nonatomic, retain) NSString *name; 
@property (nonatomic, retain) NSString *email; 
@property (nonatomic, retain) NSString *phoneNumber; 
@property (nonatomic, retain) NSString *gender; 
@property (assign) int age; 


@end 

Person.m

@implementation Person 
@synthesize name,email,phoneNumber,age,gender; 

#pragma mark 
#pragma mark NSCoder 

- (void)encodeWithCoder:(NSCoder *)encoder{ 
    [encoder encodeObject:self.name forKey:@"username"]; 
    [encoder encodeObject:self.email forKey:@"useremail"]; 
    [encoder encodeObject:self.phoneNumber forKey:@"userphonenumber"]; 
    [encoder encodeObject:self.gender forKey:@"usergender"]; 

    [encoder encodeInt:self.age forKey:@"userage"]; 
} 

- (id)initWithCoder:(NSCoder *)decoder { 
    if(self = [super init]){ 

     self.name = [decoder decodeObjectForKey:@"username"]; 
     self.email = [decoder decodeObjectForKey:@"useremail"]; 
     self.phoneNumber = [decoder decodeObjectForKey:@"userphonenumber"]; 
     self.gender = [decoder decodeObjectForKey:@"usergender"]; 

     self.age = [decoder decodeIntForKey:@"userage"]; 
    } 
    return self; 
} 

@end 

任何想法，爲什麼會發生？

Answer 1

有非常具體的限制，什麼類型的數據可以在NSDictionary內同步到NSUserDefaults。這些包括NSString, NSNumber, NSData, NSArray and NSDictionary。使用NSCoder方法序列化爲NSData（使用NSKeyedArchiver），然後儲存在NSUserDefaults中。

而且，看看this