从Javascript中删除空白行会提高性能吗？

Question

I have a very large js file, approximately 1200 lines, and some of the code is written like this (with the spaces):

function a () {



           alert("aaaa");



}


function b () {

                                                 alert("bbbb");

}

If I delete the empty lines, will it improve the speed of the web site? I have looked at other js files, for example open the source on google, and there is no empty lines and spaces. So tell me please will this improve the performance of the site?

Answer 1

White spaces are not effect the performance of a javascript file. But, if you have many characters of spaces (" ") the file size might be larger and the browser will have to load a larger file, which take more time.

If you want to minimize your file as much as you can, just search google Javascript minifier .

Good Luck!

Answer 2

It will make it take a little less time for the script to reach the client, but the performance improvement will be so small as to be unnoticeable.

You should get rid of the blank lines anyway because that's weird.

Answer 3

By removing surplus characters (blank spaces, carriage returns, comments etc), you are reducing the file size of the file, which means it can be downloaded quicker.

This process is called minification . There are lots of tools on the internet to do this for you.

Minification (and related, obfuscation ) are best practises to speed up your website.

Answer 4

JavaScript will not perform any better or worse with additional whitespace. The only gain in compressing a JS file is in reducing the loading time. A file that might originate as 1MB might be reducable to 100KB* which would be much faster to load.

_{* example only}

Answer 5

For relatively small files or small amounts of whitespace the difference will not be huge but it does take slightly longer to parse and use slightly more memory. For desktop browsers it is largely negligible but it can end up being a pretty big deal for mobile browsers where the CPUs are a LOT slower and the memory is very limited.

It can also impact the cacheability of the resources on mobile if they cross certain boundaries (and mobile browsers currently cache the resources uncompressed so it's the uncompressed size that matters).