ios - 由于未捕获的异常 'NSUnknownKeyException' 而终止应用程序此类不符合 key .img 的键值编码

Question

尝试异步加载图像时出现此错误“由于未捕获的异常‘NSUnknownKeyException’而终止应用程序，原因:‘[valueForUndefinedKey:]:此类不符合键值编码关键图片'"我的代码如下

 NSString *str = "URL of an image";

    NSMutableDictionary *record = [NSMutableDictionary dictionary];
    [record setObject:str forKey:@"img"];

    record = [_array objectAtIndex:indexPath.row];



   dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH,  0ul);
    if ([record valueForKey:@"img"]) {
        NSLog(@"in if");
        cell.m_img.image =  [record valueForKey:@"img"];
    } else {
        dispatch_async(queue, ^{
             NSLog(@"in else");
            NSURL  *imageurl = [[NSURL alloc] initWithString:str];
            NSData *image = [[NSData alloc] initWithContentsOfURL:imageurl];

            dispatch_async(dispatch_get_main_queue(), ^{
                [record setValue:[UIImage imageWithData:image] forKey:@"img"];

                [tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationNone];
            });
        });
    }

请告知我哪里出错了。谢谢马约尔

Answer 1

替换

[record valueForKey:@"img"]

与

[record objectForKey:@"img"]