如何将自定义NSObject复制到NSMutableArray [英] How to copy custom NSObject into NSMutableArray

问题描述

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

我不明白这里错了.我搜索了许多教程，并且资源似乎在这里没错.

I don't understand wht's wrong here. I have searched through numerous tutorials and resources don't seem to get what's wrong here.

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

推荐答案

您忘记分配结果数组NSMutableArray *results = [[NSMutableArray alloc] init]，这应该会有所帮助.

You forgot to allocate your results array NSMutableArray *results = [[NSMutableArray alloc] init] this should help.

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

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