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javascriptasynchronousdeferred-loading

Any way to control Javascript Async Load Order?


How do I set the load and execution order of two external async Javascript files?

Given the following...

<script src="framework.js" async></script> // Larger file
<script src="scripts.js" async></script> // Small file

Though second in order scripts.js is downloading and executing before framework.js due to it's file size, but scripts.js is dependent on framework.js.

Is there a way natively to specify the load and execution order whilst still maintaining async properties?


Solution

  • You want to use defer if you want to preserve the execution order. What defer does is it async downloads the script, but defers execution till html parsing is done.

    <script src="framework.js" defer></script>
    <script src="scripts.js" defer></script>
    

    However, you may want to start creating custom bundles once the number of scripts go higher.

    You can see the difference here