javascript - 如何在 Javascript 中过滤精确值？

Question

我想要红色和大小为 4gb 的地方只输出准确的值，但我得到的地方大小为 4 gb 但颜色为绿色，请在这方面帮助我。我正在制作一个过滤器选项，我的代码是相同的，所以如果可能的话，请把它作为我的代码，否则你也可以建议我如何实现这个？

const x = [
      {
      color: "green",
      name: "123",
      size: "4gb"
     },
    {
      color: "red",
      name: "555",
      size: "4gb"
    },
     {
      color: "green",
      name: "123",
      size: "2gb"
     },
     {
      color: "blue",
      name: "111",
      size: "2gb"
    },
    {
      color: "green",
      name: "123",
      size: "4gb"
    },
    {
      color: "red",
      name: "000",
      size: "4gb"
    }
  ]

const op = [{
  key: "color",
  item: "red"
},
{
  key: "size",
  item: "4gb"
}];

const fil = x.map(l => op.map(o => l[o.key] === o.item && l)).flat().filter(Boolean);

console.log(fil);

输出应该是:

[{
  color: "red",
  name: "555",
  size: "4gb"
},{
  color: "red",
  name: "000",
  size: "4gb"
}];

Answer 1

你应该filter()而不是 map() .

您想要执行的主要操作是 filter()，这意味着结果包含的值少于或等于原始数组中的值，因此原始数组中的每个项目可能会也可能不会出现在结果中，所以如果你想要一个 1:1/0 映射。映射始终返回与描述 1:1 映射的原始数组中相同数量的值，因此得名 map()。

另外使用every()遍历过滤器。这将确保满足all/every(同样，名称告诉您是做什么的)过滤条件。

const x = [
  {
    color: "green",
    name: "123",
    size: "4gb",
  },
  {
    color: "red",
    name: "555",
    size: "4gb",
  },
  {
    color: "green",
    name: "123",
    size: "2gb",
  },
  {
    color: "blue",
    name: "111",
    size: "2gb",
  },
  {
    color: "green",
    name: "123",
    size: "4gb",
  },
  {
    color: "red",
    name: "000",
    size: "4gb",
  },
];

const op = [
  {
    key: "color",
    item: "red",
  },
  {
    key: "size",
    item: "4gb",
  },
];

const fil = x.filter(option => op.every(({key, item}) => option[key] === item));
console.log(fil);

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