JSFiddle - React, Tailwind, and code Playground

HTML

<form onsubmit="return false;">
    <input type="text"/>
    <input type="submit"/>
</form>
<div class="errors"></div>

JavaScript

$('form').submit(function() {
    if ($('input[type=text]').val() == "some_pdf.pdf") {
        window.open("http://link_to_some_pdf.com/some_pdf.pdf");
    } else if ($('input[type=text]').val() == "some_other_pdf.pdf") {
        window.open("http://link_to_some_other_pdf.com/some_other_pdf.pdf");
    }  else {
        alert("Not a valid PDF! Try again!");
    }
});