JavaScript implementation of prev and next methods for obtaining adjacent sibling nodes of an element_javascript skills

/**
* 获取相邻元素
* @param ele 参考物元素
* @param type 类型，上一个(1)or下一个(0)
* @return 返回查找到的元素Dom对象，无则返回null
*/
function getNearEle(ele, type) {
  type = type == 1 ? "previousSibling" : "nextSibling";
  var nearEle = ele[type];
  while(nearEle) {
    if(nearEle.nodeType === 1) {
      return nearEle;
    }
    nearEle = nearEle[type];
    if(!nearEle) {
      break;
    }
  }
  return null;
}
/**
* 获取当前执行对象的上一个元素
*/
function prev() {
  return getNearEle(this, 1);
}
/**
* 获取当前执行对象的下一个元素
*/
function next() {
  return getNearEle(this, 0);
}
// var ele = document.getElementById("xxx");
// var prevElement = prev.call(ele);
// var nextElement = next.call(ele);