Testing for special characters JavaScript

Question

Say I have this HTML element:

<td>&mdash;</td>

When parsed by browsers, — is converted to an actual em-dash, like so:

<td>—</td>

How can I test for — without using other characters in my JavaScript code?

console.log(elem.innerHTML == "—"); // false
console.log(elem.textContent == "—"); // false
console.log(elem.innerHTML == "—"); // true
console.log(elem.textContent == "—"); // true

Answer 1

You could create a new DOM element, and compare the two:

/**
 * Test that a DOM element's inner HTML is === —
 */
function mdashTest(el) {
    var tempEl = document.createElement('div');
    tempEl.innerHTML = '—';

    return el.innerHTML === tempEl.innerHTML;
}

// Test it!
elem = document.getElementById('dash');
alert( mdashTest( elem ) );

<div id="dash">&mdash;</div>