如果url有效，如何检查iphone应用程序然后加载WebVIew else show alert

Posted 2021-04-07

我有应用程序我想要当用户在文本字段中输入url并按回车键时应该检查url是否有效然后在web视图中加载url否则show alert输入有效的url

在我的代码中，它始终显示有效的URL。

 - (BOOL)textFieldShouldReturn:(UITextField *)textField
  {
   [textField setUserInteractionEnabled:YES];
   [textField resignFirstResponder];

test=textField.text;

NSLog(@"Test is working and test is %@",test);

[self  urlIsValiad:test];

if ([test isEqualToString:@"Valid"]) {
    NSURL *url = [NSURL URLWithString:test]; 
    NSURLRequest *request = [NSURLRequest requestWithURL:url]; 
    [webView setScalesPageToFit:YES];         
    [self.webView loadRequest:request]; 
}
 else{

  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Please enter Valid URL" message:@"" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [alert show];
    [alert release];
}
  return YES;
}
- (BOOL) urlIsValiad: (NSString *) url 
{
NSString *regex = 
@"((?:http|https)://)?(?:www\.)?[\w\d\-_]+\.\w{2,3}(\.\w{2})?(/(?<=/)(?:[\w\d\-./_]+)?)?";
/// OR use this 
///NSString *regex = "(http|ftp|https)://[w-_]+(.[w-_]+)+([w-.,@?^=%&:/~+#]* [w-@?^=%&/~+#])?";
  NSPredicate *regextest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];

  if ([regextest evaluateWithObject: url] == YES) {
    NSLog(@"URL is valid!");

    test=@"Valid";

  }  else {
    NSLog(@"URL is not valid!");

   test=@"Not Valid";
}

return [regextest evaluateWithObject:url];
  }

答案

// .h File 
-(BOOL)validateUrl;
.m File
-(BOOL)validateUrl{
    NSString *urlRegEx =  @"((?:http|https)://)?(www\.)[\w\d\-_]+\.\w{2,3}(\.\w{2})?(/(?<=/)(?:[\w\d\-./_]+)?)?";
    NSPredicate *urlTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", urlRegEx];
    if ([urlTest evaluateWithObject: self] == YES) {
        NSLog(@"URL is valid!");
    } else {
        NSLog(@"URL is not valid!");
    }
    return [urlTest evaluateWithObject:self];
}
// Main View Controller .m File
if (![txtWebsite.text validateUrl])
    {
        [KWebsiteURLTypeValidation showAsAlert:self];
        return;
    }

另一答案

您可以使用此方法：

- (BOOL) validateUrl: (NSString *) url {
   NSString *theURL =
   @"(http|https)://((\w)*|([0-9]*)|([-|_])*)+([\.|/]((\w)*|([0-9]*)|([-|_])*))+";
   NSPredicate *urlTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", theURL]; 
   return [urlTest evaluateWithObject:url];
   }

来自Check URL validity。希望这可以帮助。

另一答案

我修改了你的代码，所以请用你的代码替换这个方法，它将超级精细

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{

   [textField setUserInteractionEnabled:YES];
   [textField resignFirstResponder];
   test=textField.text;

   NSLog(@"Test is working and test is %@",test);

   if ([self  urlIsValiad:test]) {
       NSURL *url = [NSURL URLWithString:test]; 
       NSURLRequest *request = [NSURLRequest requestWithURL:url]; 
       [webView setScalesPageToFit:YES];
       [self.webView loadRequest:request]; 
   } else {
       UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Please enter Valid URL"  message:@"" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
       [alert show];
       [alert release];
   }
  return YES;
}