TextField 특정 문자만 사용하도록 하기

Xcode의 TextField 사용할때 특정 문자만 입력 받도록 하기 위해서는 다음과 같이 한다.

예) 숫자와 영문자만 입력 받기 

#define LEGAL_TEXT @"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz "

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

     NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:LEGAL_TEXT] invertedSet];

     NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

     return [string isEqualToString:filtered];

}

예2) 숫자와 소수점만 입력 받기 (소수점이 입력된 뒤에는 숫자만 입력 받는다)

 

키패드 타입을 변경 

entryField.keyboardType = UIKeyboardTypeNumbersAndPunctuation;

#define NUMBERS @"0123456789"

#define NUMBERSPERIOD @"0123456789."

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string

{

    NSCharacterSet *cs;

    NSString *filtered;

    // Check for period

    if ([entryField.text rangeOfString:@"."].location == NSNotFound)

    {

        cs = [[NSCharacterSet characterSetWithCharactersInString:NUMBERSPERIOD] invertedSet];

        filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

        return [string isEqualToString:filtered];

    }

    // Period is in use

    cs = [[NSCharacterSet characterSetWithCharactersInString:NUMBERS] invertedSet];

    filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

    return [string isEqualToString:filtered];

}