在HTML中使用Vue并引用外部Js

思路是等所有DOM加载完毕再引用外部JS，这里使用VUE3的nextTick，并放在生命周期的mounted中实现

一、先定义一个加载函数 

//加载函数
function loadScript(url,type) {
  var script = document.createElement("script");
  script.type = type;
  script.async = "async";
  script.src = url;
  document.body.appendChild(script);
  if (script.readyState) {
    //IE
    script.onreadystatechange = function () {
      if (script.readyState == "complete" || script.readyState == "loaded") {
        script.onreadystatechange = null;
        loadnum++;
      }
    };
  } else {
    //非IE
    script.onload = function () {
        loadnum++;
    };
  }
}

二、在VUE的mounted中通过nextTick引用上面的函数

mounted(){
	//所有Dom加载完毕后执行
	this.$nextTick(()=>{
		loadScript("/dist/prism.js","text/javascript")
	})
}