遍历数组时的错误处理

Question

这里是新手。我编写了一个简单的测试函数，它遍历一堆歌曲列表，并为每个列表尝试从 Last.fm API 获取专辑封面图像。如果它不起作用，它应该在控制台中显示曲目和艺术家姓名。然而，当我运行它时，它总是显示相同的艺术家/曲目对，即最后一个迭代的，而不是触发错误的特定的。我不确定发生了什么事。

$(document).ready(function(){
array = []
for (var item in billboard) {
  var track = billboard[item]['song'];
  var artist = billboard[item]['artist'];
  $.getJSON("http://ws.audioscrobbler.com/2.0/?method=track.getInfo&api_key=myAPIkey&artist=" + artist + "&track=" + track + "&format=json&callback=?", function(data) {
      try{
        image = data.track.album.image[2]['#text'];
      }
      catch (err) {
        console.log(track + " - " artist);
        }
      });
    }
});


 var billboard = {

 "7-12-1986": {"artist": "Simply Red", "song": "Holding Back The Years"},
"6-28-1986": {"artist": "Patti LaBelle ", "song": "On My Own"},
 "7-5-1986": {"artist": "Billy Ocean", "song": "There'll Be Sad Songs (To Make You Cry)"},
 .....
 }

Answer 1

看看for and for in的区别

我认为在这种情况下你应该使用标准的 for 循环。