这个问题的答案太多了，所以我再加一个。

/**
 * parses and returns URI query parameters 
 * 
 * @param {string} param parm
 * @param {bool?} asArray if true, returns an array instead of a scalar 
 * @returns {Object|Array} 
 */
function getURIParameter(param, asArray) {
    return document.location.search.substring(1).split('&').reduce(function(p,c) {
        var parts = c.split('=', 2).map(function(param) { return decodeURIComponent(param); });
        if(parts.length == 0 || parts[0] != param) return (p instanceof Array) && !asArray ? null : p;
        return asArray ? p.concat(parts.concat(true)[1]) : parts.concat(true)[1];
    }, []);
}

用法：

getURIParameter("id")  // returns the last id or null if not present
getURIParameter("id", true) // returns an array of all ids

这将处理空参数（那些没有“=value”的键）、标量和基于数组的值检索API的公开以及正确的URI组件解码。

获取单个参数值：

function getQueryParameter(query, parameter) {
return (window.location.href.split(parameter + '=')[1].split('&')[0]);}

以json形式从window.location中的搜索对象中提取所有url参数

export const getURLParams = location => {
    const searchParams = new URLSearchParams(location.search)
    const params = {}

    for (let key of searchParams.keys()) {
        params[key] = searchParams.get(key)
    }

    return params
}

console.log(getURLParams({ search: '?query=someting&anotherquery=anotherthing' }))

// --> {query: "someting", anotherquery: "anotherthing"}

来源

function gup( name, url ) {
    if (!url) url = location.href;
    name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
    var regexS = "[\\?&]"+name+"=([^&#]*)";
    var regex = new RegExp( regexS );
    var results = regex.exec( url );
    return results == null ? null : results[1];
}
gup('q', 'hxxp://example.com/?q=abc')

window.location.href.split("?")

则忽略第一个索引

Array.prototype.slice.call(window.location.href.split("?"), 1) 

返回url参数数组

var paramArray = Array.prototype.slice.call(window.location.href.split(/[?=]+/), 1);
var paramObject = paramArray.reduce(function(x, y, i, a){ (i%2==0) ?  (x[y] = a[i+1]) : void 0; return x; }, {});

paramObject包含映射为js对象的所有参数

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] =>
)*/