如何将JavaScript对象转换为Map [String,String]？

Question

在index-dev.html我加载本地JavaScript文件:

<script type="text/javascript" src="map.js"></script>

map.js 结构上(不是字面意思)看起来像这样:

var a2b = {
  "a": "My life closed twice before its close—",
  "b": "It yet remains to see",
  "c": "If Immortality unveil",
  "d": "A third event to me",

  "e": "So huge, so hopeless to conceive",
  "f": "As these that twice befell.",
  "g": "Parting is all we know of heaven,",
  "h": "And all we need of hell.",

  "z": "Emily Dickinson, 1830-1886"
}

我想出了如何将此对象加载到Scala.js:

val a2b = js.Dynamic.global.a2b

现在a2b是类型Dynamic.我想要的是Map[String,String].

我试过这个:

val a2b = js.Dynamic.global.a2b.asInstanceOf[Map[String,String]]

但那没用.我该怎么办Map[String,String]？

Answer 1

关键是它不是一个Map,这就是为什么它不起作用.但它是一个js.Dictionary.因此,请使用它asInstanceOf代替,如果您确实需要Scala Map,请使用以下toMap函数:

val a2b = js.Dynamic.global.a2b.asInstanceOf[js.Dictionary[String]].toMap