NSURL / NSURLRequest / NSURLConnection 理解哪些方案？
Apple 表示，NSURL 是使用 RFC 1738（以及其他一些）开发的。
现在 RFC 1738 仅指定 Web URL 具有方案和方案特定部分。
我想知道 NSURL 理解的所有方案。因为我将它与 NSURLRequest 和 NSURLConnection （所谓的“URL加载器系统”）一起使用，所以我必须知道它们理解的所有方案。
为什么？因为我只是想知道。 Apple 没有在文档中详细说明这一点，只是说遵守 RFC 1738。这说明了很多，但也没有说明什么。
Apple says, NSURL is developed using RFC 1738 (and some others).
Now RFC 1738 specifies only that an web URL has a scheme and a scheme specific part.
I want to know all the schemes which NSURL understands. And because I use it with NSURLRequest and NSURLConnection (the so called "URL Loader System"), I must know all the schemes which these understand.
Why? Because I just want to know. Apple does not go into detail about it in the documentation, the just say the comply to RFC 1738. That tells a lot and also nothing.
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（2）
NSURL“支持”任何方案，因为它不知道如何使用相关方案。它只是 URL 概念的包装。同样，
NSURLRequest不知道更多，但它确实有能力存储可能特定于协议的额外信息。NSURLConnection是您开始获取更多特定于协议的地方。NSURLConnection能够支持您向其抛出的任何 URL，前提是为此注册了合适的NSURLProtocol子类。但开箱即用，记录支持http:、https:、ftp:和文件：。您可以通过快速的+canHandleRequest:调用来测试它。根据经验，系统也支持
data:URL。我已向 Apple 提交了radar://problem/13649313，要求他们记录这一点。NSURL"supports" any scheme, because it knows nothing about how to use the scheme in question. It is just a wrapper around the concept of a URL.Likewise,
NSURLRequestknows no more, but it does have capability to store extra information which could be protocol-specific.NSURLConnectionis where you start getting more protocol-specific.NSURLConnectionis capable of supporting any URL you throw at it, provided there is a suitableNSURLProtocolsubclass registered for that. But out of the box, it is documented to supporthttp:,https:,ftp:andfile:. You can test it with a quick+canHandleRequest:call.Empirically, the system supports
data:URLs too. I have filed radar://problem/13649313 with Apple asking them to document this.内置的 URL 协议可以处理
http、https、file、ftp、about 等方案和数据。您可以使用
NSURLProtocol类定义自己的协议，使 NSURL 系统自动处理新方案。The built-in URL protocols can handle the schemes
http,https,file,ftp,about, anddata.You can define your own protocols to make the NSURL system automatically handle new schemes using the
NSURLProtocolclass.