JSFiddle - React, Tailwind, and code Playground

JavaScript

var myURL = 'http://www.example.com/index.php?q=test&=Go';    

function gup( name )
    {
      name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
      var regexS = "[\\?&]"+name+"=([^&#]*)";
      var regex = new RegExp( regexS );
      var results = regex.exec( myURL );
      if( results == null )
        return "";
      else
        return results[1];
    }

    var my_param = gup( 'q' );
console.log(my_param);