When should I use NSURL instead of NSString and vice versa?

Question

This is not a question about a pertinent problem. It\'s a question by which I try to deepen my understanding of Objective-C or more specific Cocoa Foundation.

When d

Answer 1

Generally for path related operations you should prefer NSURL over NSString because the path information can be stored more efficiently in NSURL (according to the class reference for NSFileManager). So I would recommend that for your APIs you use also NSURL.

Also NSURL has URLByAppendingPathComponent: and URLByAppendingPathExtension: so convenience is served as well :-)

Answer 2

NSUrl knows how to handle virtually any king of urls — not just Web-adresses and splits it into easy accessible chunks:

• protocol or scheme (http, ftp, telnet,ssh)
• username and the password (for example for ssh: ssh://user:password@host.domain.org)
• host name
• port
• path
• GET parameters

Now you can easily asks the url-object for this chunks, while in a string there might be the need for excessive if rules or complicated regex's.