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] =>
)*/

最短路径：

new URL(location.href).searchParams.get("my_key");

优雅、实用的解决方案

让我们创建一个包含URL参数名作为关键字的对象，然后我们可以通过其名称轻松提取参数：

// URL: https://example.com/?test=true&orderId=9381  

// Build an object containing key-value pairs
export const queryStringParams = window.location.search
  .split('?')[1]
  .split('&')
  .map(keyValue => keyValue.split('='))
  .reduce<QueryStringParams>((params, [key, value]) => {
    params[key] = value;
    return params;
  }, {});

type QueryStringParams = {
  [key: string]: string;
};


// Return URL parameter called "orderId"
return queryStringParams.orderId;

这是一种只检查一个参数的简单方法：

示例URL:

http://myserver/action?myParam=2

Javascript示例：

var myParam = location.search.split('myParam=')[1]

如果URL中存在“myParam”。。。变量myParam将包含“2”，否则将未定义。

在这种情况下，可能需要一个默认值：

var myParam = location.search.split('myParam=')[1] ? location.search.split('myParam=')[1] : 'myDefaultValue';

更新：这更有效：

var url = "http://www.example.com/index.php?myParam=384&login=admin"; // or window.location.href for current url
var captured = /myParam=([^&]+)/.exec(url)[1]; // Value is in [1] ('384' in our case)
var result = captured ? captured : 'myDefaultValue';

即使URL中充满了参数，它也能正常工作。

// Read a page's GET URL variables and return them as an associative array.
function getUrlVars()
{
    var vars = [], hash;
    var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
    for(var i = 0; i < hashes.length; i++)
    {
        hash = hashes[i].split('=');
        vars.push(hash[0]);
        vars[hash[0]] = hash[1];
    }
    return vars;
}

// Usage for URL: http://my.site.com/location?locationId=53cc272c0364aefcb78756cd&shared=false
var id = getUrlVars()["locationId"];

从这里得到：http://jquery-howto.blogspot.ru/2009/09/get-url-parameters-values-with-jquery.html

我很早以前就发现了这一点，非常简单：

function getUrlVars() {
    var vars = {};
    var parts = window.location.href.replace(/[?&]+([^=&]+)=([^&]*)/gi,    
    function(m,key,value) {
      vars[key] = value;
    });
    return vars;
  }

然后这样称呼：

var fType = getUrlVars()["type"];