上面的功能工作顺利,如果您只加载一个脚本,或者您不关心多个脚本的加载顺序. 如果您有某些脚本依赖于其他,您需要使用承诺来指定加载顺序. 背后的原因是JavaScript加载资源如脚本和图像无同步。

因此,这里是另一个动态LoadScript的版本,保证下载命令:

// Based on: https://javascript.info/promise-basics#example-loadscript
function dynamicallyLoadScript(url) {
  return new Promise(function(resolve, reject) {
    var script = document.createElement("script");
    script.src = url;
    script.onload = resolve;
    script.onerror = () => reject(new Error(`Error when loading ${url}!`));
    document.body.appendChild(script);
  });
}

dynamicallyLoadScript("script1.js")
  .then(() => dynamicallyLoadScript("script2.js"))
  .then(() => dynamicallyLoadScript("script3.js"))
  .then(() => dynamicallyLoadScript("script4.js"))
  .then(() => dynamicallyLoadScript("script5.js"))
//...

现在,脚本按 script1.js、 script2.js、 script3.js 等顺序加载。

dynamicallyLoadScript("script1.js")
  .then(() => dynamicallyLoadScript("script2.js"))
  .then(() => foo()) // foo can be a function defined in either script1, script2
  .then(() => dynamicallyLoadScript("script3.js"))
  .then(() => {
     if (var1){ // var1 can be a global variable defined in either script1, script2, or script3
          bar(var1); // bar can be a function defined in either script1, script2, or script3
     } else {
          foo(var1);
     }
  })
//more .then chains...

要显示未经处理的承诺拒绝(错误加载脚本等),将此未经处理的拒绝事件听器放在代码的顶部:

// Based on: https://javascript.info/promise-error-handling#unhandled-rejections
window.addEventListener('unhandledrejection', function(event) {
  // the event object has two special properties:
  console.error(event.promise);// the promise that generated the error
  console.error(event.reason); // the unhandled error object
});

短短功能

function dynamicallyLoadScripts(urls) {
  if (urls.length === 0)
    return;

  let promise = dynamicallyLoadScript(urls[0]);
  urls.slice(1).forEach(url => {
    promise = promise.then(() => dynamicallyLoadScript(url));
  });
}

要使用它,只需通过一系列脚本URL如下:

const scriptURLs = ["dist/script1.js", "dist/script2.js", "dist/script3.js"];
dynamicallyLoadScripts(scriptURLs);

对于 Node.js 而言,这对我来说是最好的!

我在这里尝试了很多解决方案,但没有一个帮助我只是能够在没有改变范围的情况下加载另一个文件。

const fs = require('fs');
eval(fs.readFileSync('file.js') + '');

这就是简单的:

var js = document.createElement("script");

js.type = "text/javascript";
js.src = jsFilePath;

document.body.appendChild(js);

也许你可以使用我在此页面上发现的这个功能 如何将JavaScript文件纳入JavaScript文件中?

function include(filename)
{
    var head = document.getElementsByTagName('head')[0];

    var script = document.createElement('script');
    script.src = filename;
    script.type = 'text/javascript';

    head.appendChild(script)
}

var xxx = require("../lib/your-library.js")

或

import xxx from "../lib/your-library.js" //get default export
import {specificPart} from '../lib/your-library.js' //get named export
import * as _name from '../lib/your-library.js'  //get full export to alias _name

还有 Head.js. 很容易处理:

head.load("js/jquery.min.js",
          "js/jquery.someplugin.js",
          "js/jquery.someplugin.css", function() {
  alert("Everything is ok!");
});

正如你所看到的,它比 Require.js 更容易,而且像 jQuery 的 $.getScript 方法一样方便,它还有一些先进的功能,如条件加载、功能检测等。