javascript - 如何将 JavaScript 变量替换为 JSPath 表达式

Question

我正在尝试编写一个 JavaScript 函数来读取 JSON 文件，并通过将值与用户输入的字符串进行匹配来检索信息。为了导航 JSON 文件，我使用了 JSPath，但是我不知道如何使用函数在 JSPath 谓词中传递的字符串变量。

这是我目前拥有的代码:

function retrieveCategoryWinners(query) {
  var category = query
  var jsonDoc = $.getJSON("nobel.json")
  var winners = JSPath.apply('.prizes{.category === $query}.laureates', jsonDoc,
      {query: category})

JSON 文件的片段:

{
    "prizes": [
        {
            "year": "2017",
            "category": "physics",
            "laureates": [
                {
                    "id": "941",
                    "firstname": "Rainer",
                    "surname": "Weiss",
                    "motivation": "\"for decisive contributions to the LIGO detector and the observation of gravitational waves\"",
                    "share": "2"
                },
                {
                    "id": "942",
                    "firstname": "Barry C.",
                    "surname": "Barish",
                    "motivation": "\"for decisive contributions to the LIGO detector and the observation of gravitational waves\"",
                    "share": "4"
                },
                {
                    "id": "943",
                    "firstname": "Kip S.",
                    "surname": "Thorne",
                    "motivation": "\"for decisive contributions to the LIGO detector and the observation of gravitational waves\"",
                    "share": "4"
                }
            ]
        }

因此，例如，如果查询参数是“physics”，JSPath 将返回“laureates”数组。不过，将变量代入谓词似乎行不通。

Answer 1

您的变量替换是错误的。试试 template literal像这样。

  var winners = JSPath.apply(`.prizes{.category === "${category}"}.laureates`, js,
            {query: category})