我不明白为什么我会得到NaN。是否有我遗失的东西，可能是对象，还是我的代码？
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答案 0 :(得分：0)
$ .each函数循环遍历对象根目录下的每个属性，以及对象的结构方式，并非每个属性都有嵌套的标题或字幕财产。
您要么必须一致地构建对象，要么在尝试访问它们之前检查所需的属性。