User:Mike Dillon/Scripts/params.js

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Documentation for this user script can be added at User:Mike Dillon/Scripts/params.

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/* <pre><nowiki> */

var getParameterMap = (function () {
    var urlParams = {};
    return function (url) {
        if (!url) url = ___location.href;
        if (urlParams[url]) return urlParams[url];

        var params = {};
        var search = url.split("?")[1];
        if (search) {
            // Split query string on "&"
            var kvs = search.split("&");
            for (var i in kvs) {
                var kv = kvs[i].split("=", 2);

                var key = kv[0];
                var value = unescape(kv[1]);

                if (!params[key]) {
                    params[key] = [];
                }

                params[key].push(value);
            }
        }

        urlParams[url] = params;
        return params;
    };
})();

function getParameterValues(key, url) {
    return getParameterMap(url)[key];
}

function getParameter(key, url) {
    var values = getParameterValues(key, url);
    return values ? values[0] : null;
}

function getParameterNames(url) {
    var names = [];
    for (var n in getParameterMap(url)) {
        names.push(n);
    }
    return names;
}

/* </nowiki></pre> */