JSFiddle - React, Tailwind, and code Playground

HTML

<form id="checkinput" action="#">
<input type="text" name="box" class="restrict">
<input type="button" id="submit" value="Submit"/>
    </form>

JavaScript

$(function() {
    $("#submit").click(function(e) {
        e.preventDefault();

        var badwords = ["doodoo", "peepee"];
        var inputVal = $('.restrict').val();

        if ($.inArray(inputVal, badwords) > -1) alert("success");
        else alert("fail");
    });
});