如何將自定義NSObject複製到NSMutableArray

Question

NSDictionary* json = [NSJSONSerialization 
         JSONObjectWithData:responseData 

         options:kNilOptions 
         error:&error]; 
NSArray* users = [json objectForKey:@"Users"]; 
NSEnumerator* enumerator = [users objectEnumerator]; 
id element; 
NSMutableArray *results; 
Result *fetchedResults; 
while(element = [enumerator nextObject]) { 

    // fetchedResults = [[Result alloc] init]; // i have tried commenting/uncommenting 
    fetchedResults.name = (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]; 
    fetchedResults.email = (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]; 
    NSLog(@"%@", fetchedResults.name); 
    [results addObject:fetchedResults]; 

    NSLog(@"%@", (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]); // this returns valid dump 

} 
NSLog(@"%d", [results count]); // returns 0 

我不明白這裏的錯誤。我已經搜索了大量的教程和資源似乎沒有得到什麼錯誤在這裏。

編輯：

NSLog(@"%@", fetchedResults.name); // dumps null 

Answer 1

你忘了你的分配結果陣列NSMutableArray *results = [[NSMutableArray alloc] init]這應該幫助。

NSDictionary* json = [NSJSONSerialization 
        JSONObjectWithData:responseData 
        options:kNilOptions 
        error:&error]; 
NSArray* users = [json objectForKey:@"Users"]; 
NSMutableArray *results = [[NSMutableArray alloc] init]; 

for (id object in users) { 
    Result *fetchedResults = [[Result alloc] init]; 
    fetchedResults.name = (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]; 
    fetchedResults.email = (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]; 
    NSLog(@"%@", fetchedResults.name); 
    [results addObject:fetchedResults]; 
} 



NSLog(@"%@", (NSString *)[[element objectForKey:@"User"] objectForKey:@"name"]); 
} 

NSLog(@"%d", [results count]); // returns 0