Thread: Trying to validate a character user input in an array ?

Hi all, I am working on a program that prompts the user for answers to a quiz. The answers can only be a, b, c or d and they are saved to an array which I later compare to my answer key array. Below is the method I have written to get the user input and validate it but I can't seem to get the validate loop correct. The way it's written now it will always tell me that the input is invalid but then save it and continue on to the next answer prompt. If I enter something other than a, b ,c ,or d it will terminate....where I am I going wrong? Should I be validating at the String for user input or am I validating/comparing the user answers in the wrong manner? Any help is appreciated. Thank you!

public static char[] getAnswers(char arrayAnswers[ ])
	   {
		   String userInput; 
		   for (int index = 0; index < arrayUserAnswers.length; index++) {
		userInput= JOptionPane.showInputDialog("Enter the answer to question " + (index +1) + ":");
		arrayAnswers[index] = userInput.charAt(0);
			while (arrayAnswers[index]!=('a') && (arrayAnswers[index]!=('b')&& arrayAnswers[index]!=('c')&&(arrayAnswers[index]!=('d'))));
				   			{
				   				JOptionPane.showMessageDialog(null, "Please enter a valid letter!");
				   				userInput= JOptionPane.showInputDialog("Enter the answer to question " + (index +1) + ":");
				   			}
 
		}
		return arrayAnswers;
	   }

There is an array, arrayUserAnswers[], that is only used in the method to determine how many answers to gather. Don't you mean to store the user's answers in that array? The comparison you're currently doing to determine if a proper response was given is to the answer key array. Maybe that should work too, but we don't know what's in either array at this point.

BTW, The retry portion of your code will not provide an updated answer, because the new userInput value is not used.

oops sorry I missed that on my part, I've changed it to the correct arrayAnswers[] since my user answers are saved to the arrayAnswers[] (my key is actually name answerKey[i] and it's not used in this method).

Did you mean that my retry portion wouldn't return an updated answer because I was missing "arrayAnswers[index] = userInput.charAt(0);" within that loop? I've changed it but the program now prompts for an answer, regardless of the answer it will tell me it's invalid, then it prompts for answer again but it's the wrong answer #

example
1. prompt answer #1
2. input is 'a'
3. user input = invalid, <=== this wrong should validate and move to next prompt
4. prompts user again for input but this time it's for quiz answer 2 skipping gathering the correct answer 1 altogether <===this is wrong as well

public static char[] getAnswers(char arrayAnswers[ ])
	   {
		String userInput; 
		for (int index = 0; index < arrayAnswers.length; index++) {
		userInput= JOptionPane.showInputDialog("Enter the answer to question " + (index +1) + ":");
		arrayAnswers[index] = userInput.charAt(0);
			 while (arrayAnswers[index]!=('a') && (arrayAnswers[index]!=('b')&& arrayAnswers[index]!=('c')&&(arrayAnswers[index]!=('d'))));
			{
			     JOptionPane.showMessageDialog(null, "Please enter a valid letter!");
			     userInput= JOptionPane.showInputDialog("Enter the answer to question " + (index +1) + ":");
                             arrayAnswers[index] = userInput.charAt(0);
		       }
		}
		return arrayAnswers;
	   }