javascript - 交换字符串中单词的最佳方法是什么

Question

给定以下字符串，我将如何交换左右单词。

即改变

• “左”->“右”
• “右”->“左”

let str = JSON.stringify({
  val: 4,
  right: {
    val: 7,
    right: { val: 9, right: null, left: null },
    left: { val: 6, right: null, left: null },
  },
  left: {
    val: 2,
    right: { val: 3, right: null, left: null },
    left: { val: 1, right: null, left: null },
  },
}, null, 2);

str = str.replace((/"left"/g), o => { return "right1" }); 
str = str.replace((/"right"/g), o => { return "left1" });

console.log(); 
console.log(str); 

str = str.replace((/"right1"/g), o => { return "right" });

console.log(); 
console.log(str); 

str = str.replace((/"left1"/g), o => { return "left" });

我正在考虑使用 str.replace()。

Answer 1

不要使用字符串操作，保留/解析为对象并交换属性:

function swapLeftRight(obj){
  //use object deconstruction to create left and right variables, 
  //and assign them to the opposite name
  let {left:right, right:left} = obj;
  //Assign the new values
  obj.left = left, obj.right = right;
  //Use recursion if the properties are not null
  if(obj.left) swapLeftRight(obj.left);
  if(obj.right) swapLeftRight(obj.right);
}
var data = {
  val: 4,
  right: {
    val: 7,
    right: { val: 9, right: null, left: null },
    left: { val: 6, right: null, left: null },
  },
  left: {
    val: 2,
    right: { val: 3, right: null, left: null },
    left: { val: 1, right: null, left: null },
  }
};
swapLeftRight(data);
console.log(data);