javascript - 使用javascript map将嵌套数组扩展为行

Question

如何使用 Array.prototype.map() 来转换这个数据结构:

[
  {text: "sometext", tags: ["t1", "t2", "t3"]},
  {text: "sometext2", tags: ["t4", "t5", "t6"]}
]

进入这个数据结构？

[
  {tag: "t1", text: "sometext"},
  {tag: "t2", text: "sometext"},
  {tag: "t3", text: "sometext"},
  {tag: "t4", text: "sometext2"},
  {tag: "t5", text: "sometext2"},
  {tag: "t6", text: "sometext2"}
]

Answer 1

你可以参加(即将到来的)Array#flatMap并映射内部数组。

var data = [{ text: "sometext", tags: ["t1", "t2", "t3"] }, { text: "sometext2", tags: ["t4", "t5", "t6"] }],
    result = data.flatMap(({ text, tags }) => tags.map(tag => ({ tag, text })));

console.log(result);

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结果为 Array#reduce .

var data = [{ text: "sometext", tags: ["t1", "t2", "t3"] }, { text: "sometext2", tags: ["t4", "t5", "t6"] }],
    result = data.reduce((r, { text, tags }) => [...r, ...tags.map(tag => ({ tag, text }))], []);

console.log(result);

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