确保用户输入的格式正确？

Question

我在联系人屏幕上有一个文本字段,用户需要输入电子邮件地址给我发消息.什么是确保用户输入有效电子邮件地址的最佳方式,例如:

a@b.com / net / org / co.il
abc@gmail.com
abc@yahoo.com

等等..

谢谢

Answer 1

请尝试以下方法:

- (BOOL) validateEmail: (NSString *) candidate {
    NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";
    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
//  return 0;
    return [emailTest evaluateWithObject:candidate];
}


-(IBAction)btnTapped:(id)sender{

    if([self validateEmail:[txtEmail text]] ==1)
    {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Message" message:@"You Enter Correct Email id." delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
        [alert show];
        [alert release];

    }
    else{
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Message" message:@"You Enter Incoorect Email id." delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
        [alert show];
        [alert release];
    }
}