A objc library which gives access to the PSL (Public Suffix List).
The Public Suffix List is intended to enumerate all domain suffixes controlled by registrars.
A "public suffix" is also known by the older term effective top-level domain (eTLD).
If you use cocoapods just
pod 'KKDomain', :git => 'https://github.com/kejinlu/KKDomain.git'
else copy category files to your project
#import "NSString+KKDomain.h"
......
NSString *host = @"www.taobao.com";
NSLog(@"publicSuffix: %@",[host publicSuffix]);
NSLog(@"registeredDomain: %@",[host registeredDomain]);