how to get key from url code example

Example 1: get parameters from url

var url_string = "http://www.example.com/t.html?a=1&b=3&c=m2-m3-m4-m5"; //window.location.href
var url = new URL(url_string);
var c = url.searchParams.get("c");
console.log(c);

Example 2: get parameters from url

www.test.com/t.html?a=1&b=3&c=m2-m3-m4-m5