Javascript - Ignore punctuation and spaces in a Switch Statement

Question

I have a page with a question. The user will have to type the answer to that question in a textbox. I am using a switch statement to generate different feedback to different answers. I already managed to make it case insensitive.

Is there a way to also make it ignore punctuation and spaces?

This is the code I have:

function myFunction() {
    var text;
    var answers = document.getElementById("myInput").value.toLowerCase();
    switch (answers) {
        case "superman":
            text = "That is correct!";
            break;
        case "batman":
            text = "You must be kidding me...";
            break;
        default:
            text = "Wrong answer."
    }
    document.getElementById("comment").innerHTML = text;
}

<p>Who is Clark Kent?</p>
<input id="myInput" type="text">
<button onclick="myFunction()">Answer</button>
<p id="comment"></p>

I would like it to accept all the following answers as correct, without having to add extra cases:

"Superman", "superman", "Super Man", "Super man", "Super-Man!", "Super-man"...

possible duplicate of https://stackoverflow.com/questions/4374822/remove-all-special-characters-with-regexp — Aagam Jain, Sep 18 '18 at 10:25

Saransh Kataria · Accepted Answer · 2018-09-18T10:32:20.470

4

You could use a regex to ignore everything else that is not an alphabet.

function myFunction() {
    var text;
    var answers = document.getElementById("myInput").value.toLowerCase();
    answers = answers.replace(/[^a-z]/g, "");
    switch (answers) {
        case "superman":
            text = "That is correct!";
            break;
        case "batman":
            text = "You must be kidding me...";
            break;
        default:
            text = "Wrong answer."
    }
    document.getElementById("comment").innerHTML = text;
}

edited Sep 18 '18 at 10:32

answered Sep 18 '18 at 10:26

Saransh Kataria

1,447
12
19

@Barmar was already on it before you commented. Thanks for pointing it out though – Saransh Kataria Sep 18 '18 at 10:32
Thank you a lot. I am not familiar with regex, but this works perfectly. – MikeMichaels Sep 18 '18 at 10:50
@MikeMichaels you can read more about it in an interactive playground here: https://regexr.com/ Also, please mark the answer accepted if it works perfectly – Saransh Kataria Sep 18 '18 at 10:53

score 3 · Answer 2 · answered Sep 18 '18 at 10:27

You could match only letters and omit unwanted character. Then take convert to lower case.

function myFunction() {
    function getLetters(s) { return s.match(/[a-z]/gi).join('').toLowerCase(); }

    var text;
    var answers = document.getElementById("myInput").value.toLowerCase();
    switch (getLetters(answers)) {
        case "superman":
            text = "That is correct!";
            break;
        case "batman":
            text = "You must be kidding me...";
            break;
        default:
            text = "Wrong answer."
    }
    document.getElementById("comment").innerHTML = text;
}

<p>Who is Clark Kent?</p>
<input id="myInput" type="text">
<button onclick="myFunction()">Answer</button>
<p id="comment"></p>

Thank you very much for helping me. – MikeMichaels Sep 18 '18 at 10:49 — MikeMichaels, Sep 18 '18 at 10:49

Aagam Jain · Answer 3 · 2018-09-18T10:29:56.653

2

use this:

var desired = stringToReplace.replace(/[^\w\s]/gi, '').toLowerCase();

edited Sep 18 '18 at 10:29

answered Sep 18 '18 at 10:27

Aagam Jain

1,546
1
10
18

You also need to worry about case. – Tim Biegeleisen Sep 18 '18 at 10:27
Yeah Thanks :) @TimBiegeleisen – Aagam Jain Sep 18 '18 at 10:30
@Aagam Jain, I am sorry for such a noob question, I am still a beginner. But where should I put that? I tried placing that after "var text;" but it doesn't seem to work... – MikeMichaels Sep 18 '18 at 10:36
answers = answers.replace(/[^\w\s]/gi, ''); put this before switch statement. Thanks :) – Aagam Jain Sep 18 '18 at 10:41
Thanks for the help, mate! – MikeMichaels Sep 18 '18 at 10:49

Javascript - Ignore punctuation and spaces in a Switch Statement

3 Answers3