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Execute JavaScript Modules Synchronously Using document.createElement("script")
Calls to JavaScript files are typically asynchronous, meaning subsequent code execution may occur before the external script has loaded and been evaluated. This can lead to challenges when using functions or variables defined within the external script.
One approach to synchronous execution is to use an onload handler for the created script element. This handler will invoke the desired function or code once the script has been processed.
<code class="javascript">const script = document.createElement('script'); script.onload = () => { // Script loaded and ready console.log("Script loaded and ready"); }; script.src = "http://whatever.com/the/script.js"; document.getElementsByTagName('head')[0].appendChild(script);</code>
However, Internet Explorer does not trigger a "load" event for script tags, necessitating alternative methods for synchronization. Examples include performing an XMLHttpRequest to retrieve the script and executing it manually or inserting the script text into a dynamically created script tag.
For improved script management and handling special cases, it is recommended to consider robust script loading tools such as RequireJS or yepnope, which is now integrated with Modernizr.
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