如何驗證objective-C中的youtube網址？

Question

我想驗證YouTube網址http://www.youtube.com/watch?v=UdQfR4nsXvI。採用下面的代碼

(BOOL) validateUrl: (NSString *) candidate 
{ 

NSString *urlRegEx = @"(http|https)://((\\w)*|([0-9]*)|([-|_])*)+([\\.|/]((\\w)*|([0-9]*)|([-|_])*))+"; 

NSPredicate *urlTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", urlRegEx]; 

return [urlTest evaluateWithObject:candidate]; 

} 

我想也驗證任何YouTube網址格式....

編輯的代碼：

---

- (IBAction)uplaod_video_Action:(id)sender 
{ 
    NSURL *candidateURL = [NSURL URLWithString:youtube_Url.text]; 

    // WARNING > "test" is an URL according to RFCs, being just a path 
    // so you still should check scheme and all other NSURL attributes you need 

    if (candidateURL && candidateURL.scheme && candidateURL.host) 
    { 
     // candidate is a well-formed url with: 
     // - a scheme (like http://) 
     // - a host (like stackoverflow.com) 
     NSLog(@"hallo"); 
    } 
    else 
    { 
     UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Message" message:@"Please enter the Email" delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil]; 
     [alert show]; 

    } 

Answer 1

試這

NSString *urlRegEx = @"(^http:\/\/(?:www\.)?youtube.com\/watch\?(?=[^?]*v=\w+)(?:[^\s?]+)?$); 

Answer 2

使用regexpal.com檢查您的驗證機制

有一個上Raywenderlich.com

非常 comprehensive regex tutorial

Answer 3

嘗試使用這一

-(BOOL) validateUrl: (NSString *) candidate 
{ 

NSString *urlRegEx = @"(?<=v(=|/))([-a-zA-Z0-9_]+)|(?<=youtu.be/)([-a-zA-Z0-9_]+)"; 

NSPredicate *urlTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", urlRegEx]; 

return [urlTest evaluateWithObject:candidate]; 

}