如何驗證iphone中的textfield字符串？

Question

我想驗證字符串是否符合以下條件

1.string僅包含字符。 2.字符串不允許空格，輸入鍵和特殊字符。

Answer 1

要驗證字符，只有你可以使用此代碼

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

對於條件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]; 

對於條件2：您可以使用此委託方法

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