比较Javascript中的对象并列出差异

function compareObjects(obj1, obj2) {
  var diff = {};

  for (var key in obj1) {
    if (obj1.hasOwnProperty(key)) {
      if (!obj2.hasOwnProperty(key)) {
        diff[key] = obj1[key];
      } else if (typeof obj1[key] === 'object') {
        var subDiff = compareObjects(obj1[key], obj2[key]);
        if (Object.keys(subDiff).length > 0) {
          diff[key] = subDiff;
        }
      } else if (obj1[key] !== obj2[key]) {
        diff[key] = obj1[key];
      }
    }
  }

  for (var key in obj2) {
    if (obj2.hasOwnProperty(key) && !obj1.hasOwnProperty(key)) {
      diff[key] = obj2[key];
    }
  }

  return diff;
}

var obj1 = { name: 'John', age: 30, hobbies: ['reading', 'running'] };
var obj2 = { name: 'John', age: 35, hobbies: ['reading', 'swimming'] };

var diff = compareObjects(obj1, obj2);
console.log(diff);

{ age: 30, hobbies: { 1: 'running' } }