You need to parse an URL and return all the parameters from the URL, you can use the below javascript function:-

var getURLParameters = function(url) {
    var result = {};
    var searchIndex = url.indexOf("?");
    
    if (searchIndex == -1 ) return result;
        var sPageURL = url.substring(searchIndex +1);
        var sURLVariables = sPageURL.split('&');
        for (var i = 0; i < sURLVariables.length; i++) {       
            var sParameterName = sURLVariables[i].split('=');      
            result[sParameterName[0]] = sParameterName[1];
        }
        return result;
};

Usage:

var url = 'http://www.example.com/?id=1&user=username&password=password;
var params = getURLParameters(url);
console.log(params);

Result:

Object {id: 1, user: "username", password: "password"}