如何验证iPhone中的文本字符串？

Question

我想验证以下条件的字符串

1.string仅包含字符。 2.string不允许空格，enterkey和特殊字符。

Answer 1

要验证字符，您可以使用此代码

NSString *trimmed3 = [textfield.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
BOOL isNumeric = [trimmed3 length] >0 && [trimmed3 rangeOfCharacterFromSet:nonNumberSet].location== NSNotFound; 

if (!isNumeric) {
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"oops"
                                                    message:@"Phone no should be numeric" 
                                                   delegate: self 
                                          cancelButtonTitle: @"Continue"
                                          otherButtonTitles: nil];
    [alert show];
    [alert release];
}

Answer 2

条件1：

#define REG_EX_USERNAME_VALIDATION @"[a-zA-Z\\d]"
NSPredicate *userNameValidation = [ NSPredicate predicateWithFormat:@"SELF MATCHES %@", REG_EX_USERNAME_VALIDATION];
int retVal  = [ userNameValidation evaluateWithObject:inPasskey];  

对于条件2：您可以使用此委托方法

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
// checking for any whitespaces
if(([string rangeOfString:@" "].location != NSNotFound))
{
    return NO;
}
return YES;
}