1. 限制輸入框內(nèi)只能是數(shù)字和字母

[textField addTarget:self action:@selector(textFieldDidchange:) forControlEvents:UIControlEventEditingChanged];

- (void)textFieldDidchange:(UITextField *)textField {
    NSString *textString = textField.text;
    if (![self inputShouldLetterOrNum:textString] && textString.length > 0) {
        YFAlertMessage(@"只能是數(shù)字或者字母!");
        textField.text = self.currentText;
        return;
    }
    self.currentText = textString;
}

2. 判斷全漢字

- (BOOL)inputShouldChinese:(NSString *)inputString {
    if (inputString.length == 0) return NO;
    NSString *regex = @"[\u4e00-\u9fa5]+";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex];
    return [pred evaluateWithObject:inputString];
}

3. 判斷全數(shù)字：

- (BOOL)inputShouldNumber:(NSString *)inputString {
    if (inputString.length == 0) return NO;
    NSString *regex =@"[0-9]*";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex];
    return [pred evaluateWithObject:inputString];
}

4. 判斷全字母：

- (BOOL)inputShouldLetter:(NSString *)inputString {
    if (inputString.length == 0) return NO;
    NSString *regex =@"[a-zA-Z]*";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex];
    return [pred evaluateWithObject:inputString];
}

5. 判斷僅輸入字母或數(shù)字：

- (BOOL)inputShouldLetterOrNum:(NSString *)inputString {
    if (inputString.length == 0) return NO;
    NSString *regex =@"[a-zA-Z0-9]*";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex];
    return [pred evaluateWithObject:inputString];
}