通过 load 动态加载 JavaScript 文件

example

<script>
  var script = document.createElement("script");
  script.addEventListener("load", function(event) {
    console.log("Script finished loading and executing");
  });
  script.src = "http://example.com/example.js";
  script.async = true;
  document.getElementsByTagName("script")[0].parentNode.appendChild(script);
</script>

或者

<script>
  var script = document.createElement("script");
  script.onload = function(event) {
    console.log("Script finished loading and executing");
  };
  script.src = "http://example.com/example.js";
  script.async = true;
  document.getElementsByTagName("script")[0].parentNode.appendChild(script);
</script>