如何修剪到NSString中的URL？

Question

在調試時，我以這種方式獲得了url：

myURL   __NSCFString *  @"(\n    "http://www.worldweatheronline.com/images/wsymbols01_png_64/wsymbol_0003_white_cloud.png"\n)"  0x0a8a3510

我試圖通過方法將(\\n和\\n)替換為""

tringByReplacingOccurrencesOfString:@" (\n " withString:@""

終於我以這種方式獲得了我的網址

myURL   __NSCFString *  @"   "http://www.worldweatheronline.com/images/wsymbols01_png_64/wsymbol_0003_white_cloud.png"" 0x08c12540

但是我想要的是

myURL   __NSCFString *  @"http://www.worldweatheronline.com/images/wsymbols01_png_64/wsymbol_0003_white_cloud.png"  0x08c12540

有什么好的方法可以幫助我獲得想要的字符串？

Answer 1

這應該從字符串的末尾修剪非URL字符，並加上括號字符：

NSMutableCharacterSet* urlSet = [[NSMutableCharacterSet alloc] init];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLUserAllowedCharacterSet]];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLPasswordAllowedCharacterSet]];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLHostAllowedCharacterSet]];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLPathAllowedCharacterSet]];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLQueryAllowedCharacterSet]];
urlSet = [urlSet formUnionWithCharacterSet:[NSCharacterSet URLFragmentAllowedCharacterSet]];
urlSet = [[urlSet invertedSet] mutableCopy];
[urlSet addCharactersInString:@"()"];

myURL = [myURL stringByTrimmingCharactersInSet:urlSet];

如果實際上是反斜杠+ n而不是換行符，則可能需要在去除“ \\ n”之后執行此操作。