Javascript download file faster

Mercilessly delete unused code. If you detect that a given function is obsolete, get rid of it. This will improve download time since the file size will decrease. Also, the browser will take less time to analyze the code.

This is sort of a continuation of the previous tip. While I advised you to get rid of unused code, this one tells you to get rid of useless non-code stuff inside your JS files. What does that mean? A typical source code file—not only in JavaScript but also in any language—contains things that are meaningful to developers but quite useless to the machine. Examples include the following:. How can we solve this? The answer is to use a process called minification. Imagine if instead of sending a big file to the browser, your web server could send a zipped file to make it lighter.

That way, the browser would finish downloading the file sooner. Here's an excerpt from WebReference. Increase conversions with adaptive multivariate testing to squeeze more leads out of your exiating traffic. Quickly boost your ROI.

Improve your site's look, usability and accessibility for a more credible and successful website. Home Services Publications About Sitemap OPT Contact Us. Free Newsletter. Optimizing JavaScript for Download Speed. Code Listings Listing 9. Minimize HTTP requests by combining files and merging or embedding scripts on high traffic pages. Defer or delay loading where possible but avoid sticky pages. This way of making JavaScript download files allows users to retrieve the content provided in the text area.

The file reaches the computer device as a simple. The declared function sets a download attribute where you get to name the file. The encodeURIComponent function then encodes the content.

The click method prompts the download process to start as you click the download button. There is another option for downloading files without contacting the server. This time, we are using a JavaScript library called FileSaver. The example below presents the syntax to implement the saveAs FileSaver interface:. It sets the file to a Blob value.

For instance, it is useful for preventing sensitive information from being sent to external servers. It includes but is not limited to multimedia objects , programs , and code snippets. Remember: as Blob has size limitations based on the supported browser, FileSaver. A great method I initially forgot is merging several javascript files into one. Your browser can only have so many connections to a website open at a time — given the overhead to set up each connection, it makes sense to combine several small scripts into a larger one.

Use a script to merge the files — check out part 2 for an example script to do this. You probably should. I originally said no, because some older browsers have problems with compressed content. But the web is moving forward. Here are some additional references to dive in deeper:.

Keep your scripts lean, and read part 2 for some working examples. Learn Right, Not Rote. Home Articles Popular Calculus. Feedback Contact About Newsletter. Users hate waiting, so here are a few techniques you can use to trim down your sites. Find The Flab Like any optimization technique, it helps to measure and figure out what parts are taking the longest.

Look at the breakdown and see what is eating the majority if your bandwidth, and which files: 2. You can also filter by file type: 3.