问检查UITextField的输入是否仅为数字

EN

static bool TextIsValidValue( NSString* newText, double &value )
{
    bool result = false;

    if ( [newText isMatchedByRegex:@"^(?:|0|[1-9]\\d*)(?:\\.\\d*)?$"] ) {
        result = true;
        value = [newText doubleValue];
    }
    return result;
}

- (IBAction) doTextChanged:(id)sender;
{
    double value;
    if ( TextIsValidValue( [i_pause stringValue], value ) ) {
        [i_pause setTextColor:[NSColor blackColor]];
        // do something with the value
    } else {
        [i_pause setTextColor:[NSColor redColor]];
    }
}

BOOL valid;
NSCharacterSet *alphaNums = [NSCharacterSet decimalDigitCharacterSet];
NSCharacterSet *inStringSet = [NSCharacterSet characterSetWithCharactersInString:myInputField.text];
valid = [alphaNums isSupersetOfSet:inStringSet];    
if (!valid) // Not numeric

#pragma mark - UItextfield Delegate

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    if ([string isEqualToString:@"("]||[string isEqualToString:@")"]) {
        return TRUE;
    }

    NSLog(@"Range ==%d  ,%d",range.length,range.location);
    //NSRange *CURRANGE = [NSString  rangeOfString:string];

    if (range.location == 0 && range.length == 0) {
        if ([string isEqualToString:@"+"]) {
            return TRUE;
        }
    }
    return [self isNumeric:string];
}

-(BOOL)isNumeric:(NSString*)inputString{
    BOOL isValid = NO;
    NSCharacterSet *alphaNumbersSet = [NSCharacterSet decimalDigitCharacterSet];
    NSCharacterSet *stringSet = [NSCharacterSet characterSetWithCharactersInString:inputString];
    isValid = [alphaNumbersSet isSupersetOfSet:stringSet];
    return isValid;
}