在我的情况下（重定向到具有所有子url的新域）：：

window.location.replace("https://newdomain.com" + window.location.pathname);

$_GET: function (param) {
    var regex = new RegExp("(?:[?&]+" + param + "=)([^&]*)?", "i");
    var match = regex.exec(window.location.href);
    return match === null ? match : match[1];
}

我做了一个函数来实现这一点：

var getUrlParams = function (url) {
  var params = {};
  (url + '?').split('?')[1].split('&').forEach(function (pair) {
    pair = (pair + '=').split('=').map(decodeURIComponent);
    if (pair[0].length) {
      params[pair[0]] = pair[1];
    }
  });
  return params;
};

2017年5月26日更新，这里有一个ES7实现（使用babel预设阶段0、1、2或3运行）：

const getUrlParams = url => `${url}?`.split('?')[1]
  .split('&').reduce((params, pair) =>
    ((key, val) => key ? {...params, [key]: val} : params)
    (...`${pair}=`.split('=').map(decodeURIComponent)), {});

一些测试：

console.log(getUrlParams('https://google.com/foo?a=1&b=2&c')); // Will log {a: '1', b: '2', c: ''}
console.log(getUrlParams('/foo?a=1&b=2&c')); // Will log {a: '1', b: '2', c: ''}
console.log(getUrlParams('?a=1&b=2&c')); // Will log {a: '1', b: '2', c: ''}
console.log(getUrlParams('https://google.com/')); // Will log {}
console.log(getUrlParams('a=1&b=2&c')); // Will log {}

2018年3月26日更新，这里是一个Typescript实现：

const getUrlParams = (search: string) => `${search}?`
  .split('?')[1]
  .split('&')
  .reduce(
    (params: object, pair: string) => {
      const [key, value] = `${pair}=`
        .split('=')
        .map(decodeURIComponent)

      return key.length > 0 ? { ...params, [key]: value } : params
    },
    {}
  )

2019年2月13日更新，这里是一个与TypeScript 3一起使用的更新的TypeScript实现。

interface IParams { [key: string]: string }

const paramReducer = (params: IParams, pair: string): IParams => {
  const [key, value] = `${pair}=`.split('=').map(decodeURIComponent)

  return key.length > 0 ? { ...params, [key]: value } : params
}

const getUrlParams = (search: string): IParams =>
  `${search}?`.split('?')[1].split('&').reduce<IParams>(paramReducer, {})

    function gup() {
    var qs = document.location.search;
    qs = qs.split('+').join(' ');
    var params = {}, tokens, re = /[?&]?([^=]+)=([^&]*)/g;
    while (tokens = re.exec(qs))
        params[decodeURIComponent(tokens[1])] = decodeURIComponent(tokens[2]);
    return params;
}

像这样使用

var params = gup()

然后

params.param1
params.param2

PHP parse_str copycat..：）

// Handles also array params well
function parseQueryString(query) {
    var pars = (query != null ? query : "").replace(/&+/g, "&").split('&'),
        par, key, val, re = /^([\w]+)\[(.*)\]/i, ra, ks, ki, i = 0,
        params = {};

    while ((par = pars.shift()) && (par = par.split('=', 2))) {
        key = decodeURIComponent(par[0]);
        // prevent param value going to be "undefined" as string
        val = decodeURIComponent(par[1] || "").replace(/\+/g, " ");
        // check array params
        if (ra = re.exec(key)) {
            ks = ra[1];
            // init array param
            if (!(ks in params)) {
                params[ks] = {};
            }
            // set int key
            ki = (ra[2] != "") ? ra[2] : i++;
            // set array param
            params[ks][ki] = val;
            // go on..
            continue;
        }
        // set param
        params[key] = val;
    }

    return params;
}

var query = 'foo=1&bar=The+bar!%20&arr[]=a0&arr[]=a1&arr[s]=as&isset&arr[]=last';
var params = parseQueryString(query);
console.log(params)
console.log(params.foo)        // 1
console.log(params.bar)        // The bar!
console.log(params.arr[0])     // a0
console.log(params.arr[1])     // a1
console.log(params.arr.s)      // as
console.log(params.arr.none)   // undefined
console.log("isset" in params) // true like: isset($_GET['isset'])



/*
// in php
parse_str('foo=1&bar=The+bar!%20&arr[]=a0&arr[]=a1&arr[s]=as&isset&arr[]=last', $query);
print_r($query);

Array
(
    [foo] => 1
    [bar] => The bar!
    [arr] => Array
        (
            [0] => a0
            [1] => a1
            [s] => as
            [2] => last
        )

    [isset] =>
)*/

这是一个我觉得更可读的解决方案，但它需要一个.forEach（）填充程序，用于<IE8:

var getParams = function () {
  var params = {};
  if (location.search) {
    var parts = location.search.slice(1).split('&');

    parts.forEach(function (part) {
      var pair = part.split('=');
      pair[0] = decodeURIComponent(pair[0]);
      pair[1] = decodeURIComponent(pair[1]);
      params[pair[0]] = (pair[1] !== 'undefined') ?
        pair[1] : true;
    });
  }
  return params;
}