JavaScript generate random number except some values

Question

I\'m generating random numbers from 1 to 20 by calling generateRandom(). How can I exclude some values, say 8 and 15?

function generateRandom(mi         


        

Answer 1

Right now I'm using this and it works without causing browser issues with infinities loops, also tested in mobile devices (using Ionic/Cordova):

function getRandomIndex(usedIndexs, maxIndex) {
    var result = 0;
    var min = 0;
    var max = maxIndex - 1;
    var index = Math.floor(Math.random()*(max-min+1)+min);

    while(usedIndexs.indexOf(index) > -1) {
        if (index < max) {
            index++;
        } else {
          index = 0;
        }
    }

    return index;
}