Seemed odd I couldn\'t find this one already asked, but here it goes!
I have an html as follows:
Actually, I found the best, most-succinct, fastest, and most-compatible way using pure JavaScript (assuming you don't need to fully support IE lte 8) is the following:
var values = Array.prototype.slice.call(document.querySelectorAll('#select-meal-type option:checked'),0).map(function(v,i,a) {
return v.value;
});
UPDATE (2017-02-14):
An even more succinct way using ES6/ES2015 (for the browsers that support it):
const selected = document.querySelectorAll('#select-meal-type option:checked');
const values = Array.from(selected).map(el => el.value);