原生js实现下拉刷新

我们这里是放在vue里面的，普通的html也适用
首先定义下面几个方法

//获取滚动条的位置
          getScrollTop() {
              var scrollTop = 0;
              if(document.documentElement && document.documentElement.scrollTop) {
                  scrollTop = document.documentElement.scrollTop;
              } else if(document.body) {
                  scrollTop = document.body.scrollTop;
              }
              return scrollTop;
          },
          //获取当前范围高度
          getScrollHeight() {
              return Math.max(document.body.scrollHeight, document.documentElement.scrollHeight);
          },
          //获取可视范围高度
          getClientHeight() {
              var clientHeight = 0;
              if(document.body.clientHeight && document.documentElement.clientHeight) {
                  clientHeight = Math.min(document.body.clientHeight, document.documentElement.clientHeight);
              } else {
                  clientHeight = Math.max(document.body.clientHeight, document.documentElement.clientHeight);
              }
              return clientHeight;
          }

然后在mouthed里面调用

 let that=this;
window.onscroll = function() {
	if(that.getScrollTop() + that.getClientHeight() === that.getScrollHeight()) {
		//获取最后的id
		console.log(that.dynamics[that.dynamics.length-1].Id)
	}
}