以下为NSString的扩展方法,分别是判断字符串是否只是包含字母、是否只包含数字、是否只包含字母和数字:
//只有字母
- (BOOL)isOnlyLetters {
NSCharacterSet *letterCharacterset = [[NSCharacterSet letterCharacterSet] invertedSet];
return ([self rangeOfCharacterFromSet:letterCharacterset].location == NSNotFound);
}
//只有数字
- (BOOL)isOnlyNumbers {
NSCharacterSet *numSet = [[NSCharacterSet characterSetWithCharactersInString:@"0123456789"] invertedSet];
return ([self rangeOfCharacterFromSet:numSet].location == NSNotFound);
}
//字母和数字
- (BOOL)isOnlyAlphaNumeric {
NSCharacterSet *numAndLetterCharSet = [[NSCharacterSet alphanumericCharacterSet] invertedSet];
return ([self rangeOfCharacterFromSet:numAndLetterCharSet].location == NSNotFound);
}