URL 在不同浏览器中的最大长度是多少?

URL 在不同浏览器中的最大长度是多少? 它是否因浏览器而异?

最大 URL 长度是 HTTP 规范的一部分吗?

The longest URLs I came across are data URLs

Example image URL from Google image results (11747 characters)

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WWW FAQs: What is the maximum length of a URL? has its own answer based on empirical testing and research. The short answer is that going over 2048 characters makes Internet Explorer unhappy and thus this is the limit you should use. See the page for a long answer.

The URI RFC (of which URLs are a subset) doesn't define a maximum length, however, it does recommend that the hostname part of the URI (if applicable) not exceed 255 characters in length:

URI producers should use names that conform to the DNS syntax, even when use of DNS is not immediately apparent, and should limit these names to no more than 255 characters in length.

As noted in other posts though, some browsers have a practical limitation on the length of a URL.

In URL as UI Jakob Nielsen recommends:

the social interface to the Web relies on email when users want to recommend Web pages to each other, and email is the second-most common way users get to new sites (search engines being the most common): make sure that all URLs on your site are less than 78 characters long so that they will not wrap across a line feed.

This is not the maximum but I'd consider this a practical maximum if you want your URL to be shared.

Limit request line directive sets the maximum length of a URL. By default, it is set to 8190, which gives you a lot of room. However other servers and some browses, limit the length more.

Because all parameters are passed on the URL line, items that were in password of hidden fields will also be displayed in the URL of course. Neither mobile should be used for real security measures and should be considered cosmetic security at best.

I have experience with SharePoint 2007, 2010 and there is a limit of the length URL you can create from the server side in this case SharePoint, so it depends mostly on, 1) the client (browser, version, and OS) and 2) the server technology, IIS, Apache, etc.