Dynamically Load External Javascript File And Wait For It To Load Without Using Jquery

Imagine you're working on a project that requires loading an external JavaScript file dynamically, and you want to ensure it's fully loaded before proceeding with further actions. In this guide, we'll walk you through how to accomplish this without relying on jQuery.

When dynamically loading an external JavaScript file, it's crucial to handle the waiting process to prevent any unexpected behavior in your application. jQuery offers a convenient way to achieve this, but if you prefer a jQuery-free solution, we've got you covered.

To dynamically load an external JavaScript file without jQuery and wait for it to fully load, you can use the following script:

function loadScript(url, callback) {
    var script = document.createElement('script');
    script.type = 'text/javascript';

    if (script.readyState) {  // IE specific
        script.onreadystatechange = function() {
            if (script.readyState === 'loaded' || script.readyState === 'complete') {
                script.onreadystatechange = null;
                callback();
            }
        };
    } else {  // Other browsers
        script.onload = function() {
            callback();
        };
    }

    script.src = url;
    document.getElementsByTagName('head')[0].appendChild(script);
}

// Usage
loadScript('external.js', function() {
    // Code to execute after the script has loaded
});

In the above script, the `loadScript` function takes the URL of the external JavaScript file and a callback function as parameters. It dynamically creates a `` element, sets its `src` attribute to the provided URL, and appends it to the `` section of the document.

For browsers that support the `onload` event of the `` element, the callback function is triggered once the external script has finished loading. Additionally, for Internet Explorer compatibility, the script includes a check for the `readyState` property.

By structuring your code in this way, you can ensure that the external JavaScript file is fully loaded before executing any dependent code. This approach provides a lightweight and efficient method for handling dynamic script loading without jQuery.

Remember to replace `'external.js'` with the actual URL of the external JavaScript file you want to load. You can adapt this script to suit your specific requirements and enhance it with error handling or additional functionality as needed.

In conclusion, by following the outlined steps and utilizing the provided script, you can seamlessly incorporate the dynamic loading of external JavaScript files into your projects without the need for jQuery. This straightforward approach empowers you to control the loading process and manage dependencies efficiently while maintaining a clean and simple code structure.

We hope this guide has been helpful in expanding your knowledge and capabilities in software engineering. Happy coding!