用javascript替換URL中的參數值

今天遇到一個需要用javascript將url中的某些參數替換的需求，想起了不久前從司徒正美先生的部落格中淘到了一個parseUrl函數，正好可以藉此實現，代碼整理如下：

    //分析url    function parseURL(url) {        var a = document.createElement('a');        a.href = url;        return {            source: url,            protocol: a.protocol.replace(':', ''),            host: a.hostname,            port: a.port,            query: a.search,            params: (function () {                var ret = {},                seg = a.search.replace(/^\?/, '').split('&'),                len = seg.length, i = 0, s;                for (; i < len; i++) {                    if (!seg[i]) { continue; }                    s = seg[i].split('=');                    ret[s[0]] = s[1];                }                return ret;            })(),            file: (a.pathname.match(/\/([^\/?#]+)$/i) || [, ''])[1],            hash: a.hash.replace('#', ''),            path: a.pathname.replace(/^([^\/])/, '/$1'),            relative: (a.href.match(/tps?:\/\/[^\/]+(.+)/) || [, ''])[1],            segments: a.pathname.replace(/^\//, '').split('/')        };    }    //替換myUrl中的同名參數值    function replaceUrlParams(myUrl, newParams) {        /*        for (var x in myUrl.params) {            for (var y in newParams) {                if (x.toLowerCase() == y.toLowerCase()) {                    myUrl.params[x] = newParams[y];                }            }        }        */        for (var x in newParams) {            var hasInMyUrlParams = false;    for (var y in myUrl.params) {        if (x.toLowerCase() == y.toLowerCase()) {            myUrl.params[y] = newParams[x];            hasInMyUrlParams = true;            break;        }    }            //原來沒有的參數則追加    if (!hasInMyUrlParams) {        myUrl.params[x] = newParams[x];            }}        var _result = myUrl.protocol + "://" + myUrl.host + ":" + myUrl.port + myUrl.path + "?";        for (var p in myUrl.params) {            _result += (p + "=" + myUrl.params[p] + "&");        }        if (_result.substr(_result.length - 1) == "&") {            _result = _result.substr(0, _result.length - 1);        }        if (myUrl.hash != "") {            _result += "#" + myUrl.hash;        }        return _result;    }    //輔助輸出    function w(str) {        document.write(str + "
");    }    var myURL = parseURL('http://abc.com:8080/dir/index.html?id=255&m=hello#top');    w("myUrl.file = " + myURL.file)     // = 'index.html'     w("myUrl.hash = " + myURL.hash)     // = 'top'      w("myUrl.host = " + myURL.host)     // = 'abc.com'    w("myUrl.query = " + myURL.query)    // = '?id=255&m=hello'    w("myUrl.params = " + myURL.params)   // = Object = { id: 255, m: hello }      w("myUrl.path = " + myURL.path)     // = '/dir/index.html'      w("myUrl.segments = " + myURL.segments) // = Array = ['dir', 'index.html']    w("myUrl.port = " + myURL.port)     // = '8080'      w("myUrl.protocol = " + myURL.protocol) // = 'http'      w("myUrl.source = " + myURL.source)   // = 'http://abc.com:8080/dir/index.html?id=255&m=hello#top'    var _newUrl = replaceUrlParams(myURL, { id: 101, m: "World", page: 1,"page":2 });    w("
新url為：")    w(_newUrl); //http://abc.com:8080/dir/index.html?id=101&m=World&page=2#top