如何在 UITextFields 中设置验证

Question

我正在使用一些文本字段和文本字段验证。我在下面显示了我的代码，在此代码中单击按钮事件和所有文本字段文本保存在 Web 服务器上，在此代码验证中仅在空文本字段上运行。但我想更正电子邮件地址验证并修复所有文本字段字符长度。我尝试了很多次，但有些时间条件错误，有些时候不显示警报视图，有些时候不保存文本字段文本。怎么可能，请帮忙，谢谢

我的代码

- (IBAction)submit:(id)sender {

if(self.txname == nil || [self.txname.text isEqualToString:@""])
{
    UIAlertView *ErrorAlert = [[UIAlertView alloc] initWithTitle:@"Name"message:@"All Fields are mandatory." delegate:nil cancelButtonTitle:@"OK"otherButtonTitles:nil, nil];
    [ErrorAlert show];
    
}

 else if(self.txemail == nil || [self.txemail.text isEqualToString:@""])
{
    
    UIAlertView *ErrorAlert = [[UIAlertView alloc] initWithTitle:@"Email"message:@"All Fields are mandatory." delegate:nil cancelButtonTitle:@"OK"otherButtonTitles:nil, nil];
    [ErrorAlert show];
    

}

 else if(self.tx_phone == nil || [self.tx_phone.text isEqualToString:@""])
{
    UIAlertView *ErrorAlert = [[UIAlertView alloc] initWithTitle:@"Phone"message:@"All Fields are mandatory." delegate:nil cancelButtonTitle:@"OK"otherButtonTitles:nil, nil];
    [ErrorAlert show];
    
    
}
 else if(self.txcomment == nil || [self.txcomment.text isEqualToString:@""])
{
    UIAlertView *ErrorAlert = [[UIAlertView alloc] initWithTitle:@"Comment"message:@"All Fields are mandatory." delegate:nil cancelButtonTitle:@"OK"otherButtonTitles:nil, nil];
    [ErrorAlert show];
    
    
}


else
{


//Here YOUR URL
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:@"MY URL"]];


//create the Method "GET" or "POST"
[request setHTTPMethod:@"POST"];

//Pass The String to server(YOU SHOULD GIVE YOUR PARAMETERS INSTEAD OF MY PARAMETERS)
NSString *userUpdate =[NSString stringWithFormat:@"name=%@&email=%@&phone=%@&  comment=%@&",_txname.text,_txemail.text,_tx_phone.text,_txcomment.text,nil];



//Check The Value what we passed
NSLog(@"the data Details is =%@", userUpdate);

//Convert the String to Data
NSData *data1 = [userUpdate dataUsingEncoding:NSUTF8StringEncoding];

//Apply the data to the body
[request setHTTPBody:data1];

//Create the response and Error
NSError *err;
NSURLResponse *response;

NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&err];

NSString *resSrt = [[NSString alloc]initWithData:responseData encoding:NSASCIIStringEncoding];

//This is for Response
NSLog(@"got response==%@", resSrt);
if(resSrt)
{
    NSLog(@"got response");
    
}
else
{
    NSLog(@"faield to connect");
}
    {
        UIAlertView *ErrorAlert = [[UIAlertView alloc] initWithTitle:@"Success"message:@"All Fields are mandatory." delegate:nil cancelButtonTitle:@"OK"otherButtonTitles:nil, nil];
        [ErrorAlert show];
        
        
    }
    [self.view endEditing:YES];
    self.txname.text=@"";
    self.txemail.text=@"";
    self.tx_phone.text=@"";
    self.txcomment.text=@"";
    
   
}
}

Answer 1

喜欢

- (IBAction)submit:(id)sender {

   if (![txname hasText]) {
     [self showAlertView:@"Alert" message:@"name is empty"];
   }
   else if  (![txemail hasText])
  {
    [self showAlertView:@"Alert" message:@"email is empty"];
   }
  else if ([self isValidEmailAddress:txemail.text] == NO)
  {
  [self showAlertView:@"Alert" message:@"Invaildemail"];
  }
  else
  {
  // call webservice for succes
  }

创建警报控制器

- (void)showAlertView:(NSString*)title message:(NSString*)message
{
UIAlertController* alertMessage = [UIAlertController
    alertControllerWithTitle:title
                     message:message
              preferredStyle:UIAlertControllerStyleAlert];

UIAlertAction* yesButton = [UIAlertAction
    actionWithTitle:@"OK"
              style:UIAlertActionStyleDefault
            handler:^(UIAlertAction* action){
            }];

[alertMessage addAction:yesButton];

[self presentViewController:alertMessage animated:YES completion:nil];
}

用于电子邮件验证

-  (BOOL)isValidEmailAddress:(NSString *)emailAddress
{
 //Create a regex string
NSString *stricterFilterString = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}" ;

//Create predicate with format matching your regex string
NSPredicate *emailTest = [NSPredicatepredicateWithFormat:
                          @"SELF MATCHES %@", stricterFilterString];

//return true if email address is valid
return [emailTest evaluateWithObject:emailAddress];
}

更新

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
 if (textField == self.txname)
 {
// Prevent crashing undo bug – see note below.
if(range.length + range.location > textField.text.length)
{
    return NO;
}

NSUInteger newLength = [textField.text length] + [string length] - range.length;
return newLength <= 25;
}
 return YES;
}

Answer 2

我在我的代码中做到了，喜欢以下方式：

    - (IBAction)submit:(id)sender {

        if (![self isFormValid]) {

            return;

        }

    NSError *error;


    if (!error)
    {
        UIAlertView *signupalert = [[UIAlertView alloc]initWithTitle:@"Congratulations" message:@"Record Added Successfully" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];

        [signupalert show];

    }

}

-(BOOL)isFormValid
{

    NSString *emailRegEx =@"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";

    NSPredicate *emailTest =[NSPredicate predicateWithFormat:@"SELF MATCHES %@",emailRegEx];



    if (txname.text && txname.text.length==0)
    {
        [self showErrorMessage:@"Please enter name"];
        return NO;
    }

    else if (tx_phone.text && tx_phone.text.length!=10)
    {
        [self showErrorMessage:@"Please enter valid phone number"];
        return NO;
    }

    else if([emailTest evaluateWithObject: txemail.text]==NO)
    {
        [self showErrorMessage:@"Please enter Valid Email_id"];
        return NO;
    }
    else if (txcomment.text && txcomment.text.length==0)
    {
        [self showErrorMessage:@"Please enter comment"];
        return NO;
    }

    return YES;
}

-(void)showErrorMessage:(NSString *)message
{

        UIAlertView *alertmessage = [[UIAlertView alloc]initWithTitle:@"Error" message:message delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];

        [alertmessage show];

    }

Answer 3

   -(BOOL) NSStringIsValidEmail:(NSString *)checkEmail
 {
  BOOL stricterFilter = NO; 
  NSString *filter = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
      NSString *lstring = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
   NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
  NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
 return [emailTest evaluateWithObject:checkEmail];
 }