JavasScript URL Param Manipulation

url-params.js

// Based on results at http://jsperf.com/url-param-manipulation
// setURLParam returns a new queryString but not an entire URL

    testURL: 'https://www.test.com?i=main&mode=front&sid=de8d49b78a85a322c4155015fdce22c4&enc=+Hello%20&empty&zpac=gooberface234324&a=3&b=4&c=5&d=11&e=15',

    setURLParam: function( paramName, paramValue, urlString ) {
        setURLParam: function( paramName, paramValue, urlString ) {
        var urlParams = this.getURLParams( urlString ),
            newParams = [],
            foundParam = false;

        for (var param in urlParams) {
            if (param === paramName) {
                newParams.push([param, paramValue].join('='));
                foundParam = true;
            } else {
                newParams.push([param, urlParams[param]].join('='));
            }
        }

        if( !foundParam ) {
            newParams.push([paramName, paramValue].join('='));
        }
      
        return newParams.join('&');
    },
    },

    getURLParam: function( paramName, urlString ) {
        var match,
            pl     = /\+/g,  // Regex for replacing addition symbol with a space
            search = /([^&=]+)=?([^&]*)/g,
            decode = function (s) { return decodeURIComponent(s.replace(pl, " ")); },
            query  = urlString || window.location.search.substring(1);

        urlParams = {};
        while ( match = search.exec( query ) ) {
            if( paramName === decode( match[ 1 ] ) ) {
                return decode( match[ 2 ] );
            }
        }   

        return false;
    },

    getURLParams: function( urlString ) {
        var match,
            pl     = /\+/g,  // Regex for replacing addition symbol with a space
            search = /([^&=]+)=?([^&]*)/g,
            decode = function (s) { return decodeURIComponent(s.replace(pl, " ")); },
            query  = urlString || window.location.search.substring(1);

        urlParams = {};
        while ( match = search.exec( query ) ) {
            urlParams[ decode( match[ 1 ] ) ] = decode( match[ 2 ] );
        }   

        return urlParams;
    },