SEO - “优化你的代码，将 JS 代码放在页面底部”是否正确？
我想知道这是一个都市故事还是事实。
我听说网络爬虫在检查网络上的页面时，会在一段时间后终止以捕获可用代码（例如 html）并去检查另一个页面。所以，如果JS代码在头部，我将损失很大一部分预留的捕获时间。
如果这是真的，那么将 JS 放在头部就不好了，但也许放在底部，在 jQuery 语法中，例如 $(document).ready() 。
关于这个你能告诉我什么吗？谢谢大家！
I'd like to know if this is an urban story or if is the truth.
I've heard that web crawlers, when they inspect a page on the web, terminate after an amount of time to catch the Available code (such html) and go to inspect another page. So, if the JS code is in the head, I'll lose a huge part of the reserved time for the catching.
If that's true, it is not good put the JS on the head, but maybe in the bottom, inside a jQuery syntax such $(document).ready().
What can you tell me about this? Thanks everybody!
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您关于 javascript 应该放在文件末尾的断言是正确的，但并不是真正出于您所说的原因。
将 javascript 放在文件底部的主要原因是浏览器会在下载页面时尝试呈现该页面。但是，如果遇到 javascript，浏览器将暂停渲染以解析/运行 javascript。这可能会导致用户感觉页面加载缓慢。将 javascript 放在末尾允许浏览器在暂停解析和处理 javascript 之前渲染整个页面（或大部分）。
Your assertion that javascript should go at the end of the file is correct, but not really for the reason you state.
The primary reason for putting your javascript at the bottom of the file is that browsers try to render a page as it is being downloaded. However, if javascript is encountered the browser will pause rendering to parse/run the javascript. This can result in a user perception that the page is slow to load. Putting the javascript at the end allows the browser to render the whole page (or most of it) before pausing to parse and process the javascript.
无论这是否是一个神话，您都应该将 JavaScript 放在外部 .js 文件中
的底部。这意味着您根本不必使用$(document).ready，浏览器只会在加载正文内容后解析 JavaScript，这使得页面加载速度更快。将 JavaScript 放在中是没有意义的。Regardless of whether it's a myth or not, you should put your JavaScript at the bottom of the
<body>in an external .js file. This means you don't have to use$(document).readyat all and the browser will only parse the JavaScript after loading the body content, which makes the page-loading faster. There is no point in putting the JavaScript in the<head>.