Last Updated: February 25, 2016
·
845
· adamyanalunas

Proper URL path escaping in Cocoa

Don't do this:

NSString *escaped = [path stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

Do this:

CFStringRef escaped = CFURLCreateStringByAddingPercentEscapes(NULL,
                                                          (CFStringRef)path,
                                                          NULL,
                                                          CFSTR(";?#"),
                                                          kCFStringEncodingUTF8);

2 Responses
Add your response

Why?

over 1 year ago ·

Because stringByAddingPercentEscapesUsingEncoding alone does not strictly conform to what can be escaped in arguments and you may end up with skipped, unencoded characters in your string. That would result in a malformed URL with incorrect parameters.

That would result in great sadness. And probably sadness as well.

over 1 year ago ·