var text = 'price[5][68]';
var regex = /price\[(\d+)\]\[(\d+)\]/gi;
match = regex.exec(text);

match[1] and match[2] will contain the numbers you're looking for.

JavaScript has a RegExp object which does what you want. The String object has a match() function that will help you out.

var matches = text.match(/price\[(\d+)\]\[(\d+)\]/);
var productId = matches[1];
var shopId    = matches[2];

This should work:

var matches = text.match(/\[(\d+)\][(\d+)\]/);
var productId = matches[1];
var shopId = matches[2];

var myregexp = /\[(\d+)\]\[(\d+)\]/;
var match = myregexp.exec(text);
if (match != null) {
var productId = match[1];
var shopId = match[2];
} else {
// no match
}

var thisRegex = new RegExp('\[(\d+)\]\[(\d+)\]');


if(!thisRegex.test(text)){
alert('fail');
}

I found test to act more preg_match as it provides a Boolean return. However you do have to declare a RegExp var.

TIP: RegExp adds it's own / at the start and finish, so don't pass them.

Sample code to get image links within HTML content. Like preg_match_all in PHP

let HTML = '<div class="imageset"><table><tbody><tr><td width="50%"><img src="htt ps://domain.com/uploads/monthly_2019_11/7/1.png.jpg" class="fr-fic fr-dii"></td><td width="50%"><img src="htt ps://domain.com/uploads/monthly_2019_11/7/9.png.jpg" class="fr-fic fr-dii"></td></tr></tbody></table></div>';
let re = /<img src="(.*?)"/gi;
let result = HTML.match(re);

out array

0: "<img src="htt ps://domain.com/uploads/monthly_2019_11/7/1.png.jpg""
1: "<img src="htt ps://domain.com/uploads/monthly_2019_11/7/9.png.jpg""

Some Googling brought me to this :

function preg_match (regex, str) {
return (new RegExp(regex).test(str))
}
console.log(preg_match("^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,6}$","test"))
console.log(preg_match("^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,6}$","what@google.com"))

See https://locutus.io for more info.

get matched string back or false

function preg_match (regex, str) {
if (new RegExp(regex).test(str)){
return regex.exec(str);
}
return false;
}