Javascript代码陷入无尽的“ do while”循环中

Question

I'm working on a quiz application with Javascript with some form validation. I'm trying to make it so that if the user inputs an answer that isn't an option, the code tells the user to please put in a proper answer and the program loops back to the beginning of the question. With the way the code is written now, it loops back to the beginning of the question after input is given, even if the input is a selectable option. I'm assuming I have something wrong with the "do while loop" whether it's formatted incorrectly or something to do with the loops condition is causing the infinite looping.I'm having a hard time figuring out the problem so any help would be appreciated.

Answer 1

You need to fix your comparison (don't want question selected to be "a" nor "b'):

let score = 0;
let question1 = "";


do{
    question1 = prompt("In Empire Strikes Back, which one of luke's hand is cut off by Darth Vader? (a) Left (b) Right");
        switch(question1.toLowerCase()){
            case "a":
                alert("Sorry that's incorrect");
                break;
            case "b":
                alert("That's correct!");
                score+=1;
                break;
            default:
                alert("That answer wasn't an option, please select one of the options listed");
        }
}
while(question1 != "a" && question1 != "b");