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RegEx for matching YouTube embed ID

I'm in non-modern JavaScript and I have a string defined as follows:

"//www.youtube.com/embed/DmYK479EpQc?vq=hd720&rel=0"

I want to pull out just the DmYK479EpQc but I don't know the length. I do know that I want what is after the / and before the ?

Is there some simple lines of JavaScript that would solve this?

Solution

  • This expression might help you to do so, and it might be faster:

    (d\/)([A-z0-9]+)(\?)

    enter image description here

    Graph

    This graph shows how the expression would work and you can visualize other expressions in this link:

    enter image description here

    const regex = /(.*)(d\/)([A-z0-9]+)(\?)(.*)/gm;
const str = `//www.youtube.com/embed/DmYK479EpQc?vq=hd720&rel=0`;
const subst = `$3`;

// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);

console.log('Substitution result: ', result);

    Performance Test

    This JavaScript snippet shows the performance of that expression using a simple 1-million times for loop.

    const repeat = 1000000;
const start = Date.now();

for (var i = repeat; i >= 0; i--) {
	const string = '//www.youtube.com/embed/DmYK479EpQc?vq=hd720&rel=0';
	const regex = /(.*)(d\/)([A-z0-9]+)(\?)(.*)/gm;
	var match = string.replace(regex, "$3");
}

const end = Date.now() - start;
console.log("YAAAY! \"" + match + "\" is a match 💚💚💚 ");
console.log(end / 1000 + " is the runtime of " + repeat + " times benchmark test. 😳 ");