Lodash Get 实现

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1const a = {
2  b: {
3    c: [1, 2, 3],
4  },
5};
6
7const get = (obj, path, defaultValue = undefined) => {
8  if (path.length === 0) {
9    return obj;
10  }
11  if (!obj) {
12    return defaultValue;
13  }
14  if (typeof path === "string") {
15    path = path.replace(/\[/g, ".").replace(/\]/g, "").split(".");
16  }
17  let p = path.shift();
18  return get(obj[p], path);
19};
20
21const res = get(a, "b.c[3]");
22
23console.log(res);