Does js code appear in the website source code have an impact on seo?

Disadvantages of JS: Search engines don't recognize it.

Frankly speaking, I don't think JS has a great negative impact on SEO, as long as the website doesn't contain too many JS, because now the search engine really can't recognize such a programming language. Search engines such as Google also emphasize this point: try to use text information that search engines can recognize and avoid too many complex technologies such as JS and Cookies. Yes, mastering a degree can give full play to the beneficial side of JS to SEO.

What should I do if I want to use JS code without interfering with the crawling and recognition of search engines? In fact, this problem is not very difficult, what is important is: grasp a degree!

How to avoid this problem:

Method 1: Never use JS code to navigate again.

Put all unimportant JS on the top of the bottom body of the page to realize asynchronous loading, that is, after all pages are loaded, load these unimportant JS at last, so as not to affect the speed of the page. Navigation and other links in web pages are the focus of search engines. When the navigation uses JS code, which means that the search engine can't recognize it, you won't crawl your webpage, let alone rank it.

Method 2: Merge JS files.

Merging JS, that is, reducing HTTP requests and requesting the server once less, will be faster, while merging two originally independent JSs requires some technology.

Method 3: Lose weight for JS files.

Don't discuss what three-eye operator, reduce object search, how to make JS concise, just use JS slimming tool. Usually, such tools will compress hundreds of lines of code in JS files into one line, making the size smaller. Recommended tool: pressor.com/. Because of blank lines and other problems, sometimes using this tool will make JS function invalid. The simplest way is to put compressed JS into DW with Dreamweaver, and DW will automatically prompt you that there is an error, start a new line from the wrong place, or restore it.