將字符串轉化為變量名的方法

頭條面試題：實現一個get函數，使得下面的調用可以輸出正確的結果

const obj = { selector: { to: { toutiao: "FE Coder"} }, target: [1, 2, { name: 'byted'}]};

get(obj, 'selector.to.toutiao', 'target[0]', 'target[2].name');
// [ 'FE Coder', 1, 'byted']

簡而言之，這就是一個將字符串轉化為變量名的題目

方法一：使用eval（）函數

const obj = { selector: { to: { toutiao: "FE Coder"} }, target: [1, 2, { name: 'byted'}]};
  // [ 'FE Coder', 1, 'byted']
  //get(obj, 'selector.to.toutiao', 'target[0]', 'target[2].name');
  function get(obj,x,y,z){
    //把字符串變為變量
    x=(eval("obj."+x));
    y=(eval("obj."+y));
    z=(eval("obj."+z));
    console.log(x,y,z);
  }
  get(obj,'selector.to.toutiao','target[0]','target[2].name')

方法二：使用模板字符串 ``

function get(data, ...args) {
    const res = JSON.stringify(data);
    return args.map((item) => (new Function(`try {return ${res}.${item} } catch(e) {}`))());
  }

  const obj = { selector: { to: { toutiao: "FE Coder"} }, target: [1, 2, { name: 'byted'}]};
  console.log(get(obj, 'selector.to.toutiao', 'target[0]', 'target[2].name', 'asd'));