检查特殊字符和空格

Question

I have a hangman game created in java. I want to create a simple function that will check if the word input has white space and/or special characters.

I've found the functions String.replaceAll(), but I haven't been able to dig up a premade function that returns a boolean value for if there are special charactors and/or white space.

Is there a function out there already? Or at least a simpler way of specifying no white space or special characters other than doing the following?

public  void checkWord()
    {
        boolean flag = false;
        for(int i=0;i<wordArray.length;i++)
        {
            if(wordArray[i] == '1' || wordArray[i] == '2' || wordArray[i] == '3' || wordArray[i] == '4' || wordArray[i] == '5' || wordArray[i] == '6' || wordArray[i] == '7' || wordArray[i] == '8' || wordArray[i] == '9'  )
            {
                flag = true;
            }
        }
        if(flag == true)
        {
            System.out.println("Invalid characters used in the word");
            System.exit(0);
        }
    }

The function is getting dense, and I've only covered digits. Thoughts?

Answer 1

You can use a simple regular expression:

public boolean isValidWord(String w) {
    return w.matches("[A-Za-z]*");
}

Explanation of the regex:

[A-Za-z] - capital or lowercase letter
*        - zero or more

More info on regexes: http://www.regular-expressions.info/