是否有一种通过jQuery(或不使用)检索查询字符串值的无插件方法?

如果是,怎么办?如果没有,是否有插件可以这样做?


当前回答

可靠地做这件事比一开始想象的要复杂得多。

其他答案中使用的location.search很脆弱,应该避免使用-例如,如果有人搞砸了,并在?查询字符串。在我看来,URL在浏览器中自动转义的方式有很多种,这使得decodeURIComponent非常强制性。许多查询字符串是由用户输入生成的,这意味着对URL内容的假设非常糟糕。包括非常基本的东西,比如每个键都是唯一的,甚至有一个值。

为了解决这个问题,这里提供了一个可配置的API,并提供了健康的防御性编程。请注意,如果您愿意对某些变量进行硬编码,或者如果输入不能包含hasOwnProperty等,则可以将其大小减半。

版本1:返回包含每个参数的名称和值的数据对象。它有效地消除了重复,并始终尊重从左到右找到的第一个。

function getQueryData(url, paramKey, pairKey, missingValue, decode) {

    var query, queryStart, fragStart, pairKeyStart, i, len, name, value, result;

    if (!url || typeof url !== 'string') {
        url = location.href; // more robust than location.search, which is flaky
    }
    if (!paramKey || typeof paramKey !== 'string') {
        paramKey = '&';
    }
    if (!pairKey || typeof pairKey !== 'string') {
        pairKey = '=';
    }
    // when you do not explicitly tell the API...
    if (arguments.length < 5) {
        // it will unescape parameter keys and values by default...
        decode = true;
    }

    queryStart = url.indexOf('?');
    if (queryStart >= 0) {
        // grab everything after the very first ? question mark...
        query = url.substring(queryStart + 1);
    } else {
        // assume the input is already parameter data...
        query = url;
    }
    // remove fragment identifiers...
    fragStart = query.indexOf('#');
    if (fragStart >= 0) {
        // remove everything after the first # hash mark...
        query = query.substring(0, fragStart);
    }
    // make sure at this point we have enough material to do something useful...
    if (query.indexOf(paramKey) >= 0 || query.indexOf(pairKey) >= 0) {
        // we no longer need the whole query, so get the parameters...
        query = query.split(paramKey);
        result = {};
        // loop through the parameters...
        for (i = 0, len = query.length; i < len; i = i + 1) {
            pairKeyStart = query[i].indexOf(pairKey);
            if (pairKeyStart >= 0) {
                name = query[i].substring(0, pairKeyStart);
            } else {
                name = query[i];
            }
            // only continue for non-empty names that we have not seen before...
            if (name && !Object.prototype.hasOwnProperty.call(result, name)) {
                if (decode) {
                    // unescape characters with special meaning like ? and #
                    name = decodeURIComponent(name);
                }
                if (pairKeyStart >= 0) {
                    value = query[i].substring(pairKeyStart + 1);
                    if (value) {
                        if (decode) {
                            value = decodeURIComponent(value);
                        }
                    } else {
                        value = missingValue;
                    }
                } else {
                    value = missingValue;
                }
                result[name] = value;
            }
        }
        return result;
    }
}

版本2:返回一个具有两个相同长度数组的数据映射对象,一个用于名称,另一个用于值,每个参数都有一个索引。此格式支持重复名称,并故意不消除重复名称,因为这可能就是您希望使用此格式的原因。

function getQueryData(url, paramKey, pairKey, missingValue, decode) {

    var query, queryStart, fragStart, pairKeyStart, i, len, name, value, result;

    if (!url || typeof url !== 'string') {
          url = location.href; // more robust than location.search, which is flaky
    }
        if (!paramKey || typeof paramKey !== 'string') {
            paramKey = '&';
        }
        if (!pairKey || typeof pairKey !== 'string') {
            pairKey = '=';
        }
        // when you do not explicitly tell the API...
        if (arguments.length < 5) {
            // it will unescape parameter keys and values by default...
            decode = true;
        }

        queryStart = url.indexOf('?');
        if (queryStart >= 0) {
            // grab everything after the very first ? question mark...
            query = url.substring(queryStart + 1);
        } else {
            // assume the input is already parameter data...
            query = url;
        }
        // remove fragment identifiers...
        fragStart = query.indexOf('#');
        if (fragStart >= 0) {
            // remove everything after the first # hash mark...
            query = query.substring(0, fragStart);
        }
        // make sure at this point we have enough material to do something useful...
        if (query.indexOf(paramKey) >= 0 || query.indexOf(pairKey) >= 0) {
            // we no longer need the whole query, so get the parameters...
            query = query.split(paramKey);
            result = {
                names: [],
                values: []
            };
            // loop through the parameters...
            for (i = 0, len = query.length; i < len; i = i + 1) {
                pairKeyStart = query[i].indexOf(pairKey);
                if (pairKeyStart >= 0) {
                    name = query[i].substring(0, pairKeyStart);
                } else {
                    name = query[i];
                }
                // only continue for non-empty names...
                if (name) {
                    if (decode) {
                        // unescape characters with special meaning like ? and #
                        name = decodeURIComponent(name);
                    }
                    if (pairKeyStart >= 0) {
                        value = query[i].substring(pairKeyStart + 1);
                        if (value) {
                            if (decode) {
                                value = decodeURIComponent(value);
                            }
                        } else {
                            value = missingValue;
                        }
                    } else {
                        value = missingValue;
                    }
                    result.names.push(name);
                    result.values.push(value);
                }
           }
           return result;
       }
   }

其他回答

这是我在GitHub上的查询字符串解析代码版本。

它的前缀是jquery.*,但解析函数本身不使用jquery。它非常快,但仍然可以进行一些简单的性能优化。

它还支持URL中的列表和哈希表编码,例如:

arr[]=10&arr[]=20&arr[]=100

or

hash[key1]=hello&hash[key2]=moto&a=How%20are%20you

jQuery.toQueryParams = function(str, separator) {
    separator = separator || '&'
    var obj = {}
    if (str.length == 0)
        return obj
    var c = str.substr(0,1)
    var s = c=='?' || c=='#'  ? str.substr(1) : str; 

    var a = s.split(separator)
    for (var i=0; i<a.length; i++) {
        var p = a[i].indexOf('=')
        if (p < 0) {
            obj[a[i]] = ''
            continue
        }
        var k = decodeURIComponent(a[i].substr(0,p)),
            v = decodeURIComponent(a[i].substr(p+1))

        var bps = k.indexOf('[')
        if (bps < 0) {
            obj[k] = v
            continue;
        } 

        var bpe = k.substr(bps+1).indexOf(']')
        if (bpe < 0) {
            obj[k] = v
            continue;
        }

        var bpv = k.substr(bps+1, bps+bpe-1)
        var k = k.substr(0,bps)
        if (bpv.length <= 0) {
            if (typeof(obj[k]) != 'object') obj[k] = []
            obj[k].push(v)
        } else {
            if (typeof(obj[k]) != 'object') obj[k] = {}
            obj[k][bpv] = v
        }
    }
    return obj;

}

这里发布的一些解决方案效率低下。每次脚本需要访问参数时重复正则表达式搜索是完全不必要的,一个函数将参数拆分为关联数组样式对象就足够了。如果您不使用HTML5历史API,则每次加载页面只需要一次。这里的其他建议也无法正确解码URL。

var urlParams;
(window.onpopstate = function () {
    var match,
        pl     = /\+/g,  // Regex for replacing addition symbol with a space
        search = /([^&=]+)=?([^&]*)/g,
        decode = function (s) { return decodeURIComponent(s.replace(pl, " ")); },
        query  = window.location.search.substring(1);
  
    urlParams = {};
    while (match = search.exec(query))
       urlParams[decode(match[1])] = decode(match[2]);
})();

示例查询字符串:

?i=main&mode=front&sid=de8d49b78a85a322c4155015fdce22c4&enc=+Hello%20&empty

结果:

 urlParams = {
    enc: " Hello ",
    i: "main",
    mode: "front",
    sid: "de8d49b78a85a322c4155015fdce22c4",
    empty: ""
}

alert(urlParams["mode"]);
// -> "front"

alert("empty" in urlParams);
// -> true

这也可以很容易地改进为处理数组样式的查询字符串。这里有一个这样的例子,但由于RFC 3986中没有定义数组样式参数,所以我不会用源代码污染这个答案。对于那些对“污染”版本感兴趣的人,请看下面坎贝尔的答案。

此外,正如评论中指出的;是key=value对的合法分隔符。它需要更复杂的正则表达式来处理;或&,我认为这是不必要的,因为这很少见;我想说,更不可能两者都使用。如果您需要支持;而不是&,只是在正则表达式中交换它们。


If you're using a server-side preprocessing language, you might want to use its native JSON functions to do the heavy lifting for you. For example, in PHP you can write:
<script>var urlParams = <?php echo json_encode($_GET, JSON_HEX_TAG);?>;</script>

简单多了!

#已更新

一个新的功能是检索重复的参数,如下myparam=1和myparam=2。然而,没有一个规范,目前的大多数方法都遵循数组的生成。

myparam = ["1", "2"]

因此,这是管理它的方法:

let urlParams = {};
(window.onpopstate = function () {
    let match,
        pl = /\+/g,  // Regex for replacing addition symbol with a space
        search = /([^&=]+)=?([^&]*)/g,
        decode = function (s) {
            return decodeURIComponent(s.replace(pl, " "));
        },
        query = window.location.search.substring(1);

    while (match = search.exec(query)) {
        if (decode(match[1]) in urlParams) {
            if (!Array.isArray(urlParams[decode(match[1])])) {
                urlParams[decode(match[1])] = [urlParams[decode(match[1])]];
            }
            urlParams[decode(match[1])].push(decode(match[2]));
        } else {
            urlParams[decode(match[1])] = decode(match[2]);
        }
    }
})();

ES2015(ES6)

getQueryStringParams = query => {
    return query
        ? (/^[?#]/.test(query) ? query.slice(1) : query)
            .split('&')
            .reduce((params, param) => {
                    let [key, value] = param.split('=');
                    params[key] = value ? decodeURIComponent(value.replace(/\+/g, ' ')) : '';
                    return params;
                }, {}
            )
        : {}
};

没有jQuery

var qs = (function(a) {
    if (a == "") return {};
    var b = {};
    for (var i = 0; i < a.length; ++i)
    {
        var p=a[i].split('=', 2);
        if (p.length == 1)
            b[p[0]] = "";
        else
            b[p[0]] = decodeURIComponent(p[1].replace(/\+/g, " "));
    }
    return b;
})(window.location.search.substr(1).split('&'));

URL如下?topic=123&name=query+string,将返回以下内容:

qs["topic"];    // 123
qs["name"];     // query string
qs["nothere"];  // undefined (object)

Google方法

撕扯谷歌的代码,我找到了他们使用的方法:getUrlParameters

function (b) {
    var c = typeof b === "undefined";
    if (a !== h && c) return a;
    for (var d = {}, b = b || k[B][vb], e = b[p]("?"), f = b[p]("#"), b = (f === -1 ? b[Ya](e + 1) : [b[Ya](e + 1, f - e - 1), "&", b[Ya](f + 1)][K](""))[z]("&"), e = i.dd ? ia : unescape, f = 0, g = b[w]; f < g; ++f) {
        var l = b[f][p]("=");
        if (l !== -1) {
            var q = b[f][I](0, l),
                l = b[f][I](l + 1),
                l = l[Ca](/\+/g, " ");
            try {
                d[q] = e(l)
            } catch (A) {}
        }
    }
    c && (a = d);
    return d
}

这是模糊的,但可以理解。它无法工作,因为某些变量未定义。

他们开始在url上查找参数?并且还从散列#中。然后,对于每个参数,它们以等号b[f][p](“=”)分割(看起来像indexOf,它们使用字符的位置来获取键/值)。拆分后,他们检查参数是否有值,如果有值,则存储d的值,否则继续。

最后返回对象d,处理转义和+符号。这个对象和我的一样,它有相同的行为。


我的方法作为jQuery插件

(function($) {
    $.QueryString = (function(paramsArray) {
        let params = {};

        for (let i = 0; i < paramsArray.length; ++i)
        {
            let param = paramsArray[i]
                .split('=', 2);
            
            if (param.length !== 2)
                continue;
            
            params[param[0]] = decodeURIComponent(param[1].replace(/\+/g, " "));
        }
            
        return params;
    })(window.location.search.substr(1).split('&'))
})(jQuery);

用法

//Get a param
$.QueryString.param
//-or-
$.QueryString["param"]
//This outputs something like...
//"val"

//Get all params as object
$.QueryString
//This outputs something like...
//Object { param: "val", param2: "val" }

//Set a param (only in the $.QueryString object, doesn't affect the browser's querystring)
$.QueryString.param = "newvalue"
//This doesn't output anything, it just updates the $.QueryString object

//Convert object into string suitable for url a querystring (Requires jQuery)
$.param($.QueryString)
//This outputs something like...
//"param=newvalue&param2=val"

//Update the url/querystring in the browser's location bar with the $.QueryString object
history.replaceState({}, '', "?" + $.param($.QueryString));
//-or-
history.pushState({}, '', "?" + $.param($.QueryString));

性能测试(针对正则表达式方法的拆分方法)(jsPerf)

准备代码:方法声明

拆分测试代码

var qs = window.GetQueryString(query);

var search = qs["q"];
var value = qs["value"];
var undef = qs["undefinedstring"];

Regex测试代码

var search = window.getParameterByName("q");
var value = window.getParameterByName("value");
var undef = window.getParameterByName("undefinedstring");

在Windows Server 2008 R2/7 x64上的Firefox 4.0 x86中测试

拆分方法:最快144780±2.17%Regex方法:13891±0.85%|90%慢

使用纯JavaScript和正则表达式的简单解决方案:

alert(getQueryString("p2"));

function getQueryString (Param) {
    return decodeURI("http://www.example.com/?p1=p11&p2=p2222".replace(new RegExp("^(?:.*[&?]" + encodeURI(Param).replace(/[.+*]/g, "$&") + "(?:=([^&]*))?)?.*$", "i"), "$1"));
}

Js投标

这些都是很好的答案,但我需要一些更强大的东西,我想你们可能都想拥有我创造的东西。

这是一种简单的库方法,可以对URL参数进行剖析和操作。静态方法有以下子方法,可以在主题URL上调用:

获取主机获取路径获取哈希setHash获取参数获取查询setParam(设置参数)获取参数hasParamremoveParam(删除参数)

例子:

URLParser(url).getParam('myparam1')

var url = "http://www.example.com/folder/mypage.html?myparam1=1&myparam2=2#something";

function URLParser(u){
    var path="",query="",hash="",params;
    if(u.indexOf("#") > 0){
        hash = u.substr(u.indexOf("#") + 1);
        u = u.substr(0 , u.indexOf("#"));
    }
    if(u.indexOf("?") > 0){
        path = u.substr(0 , u.indexOf("?"));
        query = u.substr(u.indexOf("?") + 1);
        params= query.split('&');
    }else
        path = u;
    return {
        getHost: function(){
            var hostexp = /\/\/([\w.-]*)/;
            var match = hostexp.exec(path);
            if (match != null && match.length > 1)
                return match[1];
            return "";
        },
        getPath: function(){
            var pathexp = /\/\/[\w.-]*(?:\/([^?]*))/;
            var match = pathexp.exec(path);
            if (match != null && match.length > 1)
                return match[1];
            return "";
        },
        getHash: function(){
            return hash;
        },
        getParams: function(){
            return params
        },
        getQuery: function(){
            return query;
        },
        setHash: function(value){
            if(query.length > 0)
                query = "?" + query;
            if(value.length > 0)
                query = query + "#" + value;
            return path + query;
        },
        setParam: function(name, value){
            if(!params){
                params= new Array();
            }
            params.push(name + '=' + value);
            for (var i = 0; i < params.length; i++) {
                if(query.length > 0)
                    query += "&";
                query += params[i];
            }
            if(query.length > 0)
                query = "?" + query;
            if(hash.length > 0)
                query = query + "#" + hash;
            return path + query;
        },
        getParam: function(name){
            if(params){
                for (var i = 0; i < params.length; i++) {
                    var pair = params[i].split('=');
                    if (decodeURIComponent(pair[0]) == name)
                        return decodeURIComponent(pair[1]);
                }
            }
            console.log('Query variable %s not found', name);
        },
        hasParam: function(name){
            if(params){
                for (var i = 0; i < params.length; i++) {
                    var pair = params[i].split('=');
                    if (decodeURIComponent(pair[0]) == name)
                        return true;
                }
            }
            console.log('Query variable %s not found', name);
        },
        removeParam: function(name){
            query = "";
            if(params){
                var newparams = new Array();
                for (var i = 0;i < params.length;i++) {
                    var pair = params[i].split('=');
                    if (decodeURIComponent(pair[0]) != name)
                          newparams .push(params[i]);
                }
                params = newparams;
                for (var i = 0; i < params.length; i++) {
                    if(query.length > 0)
                        query += "&";
                    query += params[i];
                }
            }
            if(query.length > 0)
                query = "?" + query;
            if(hash.length > 0)
                query = query + "#" + hash;
            return path + query;
        },
    }
}

document.write("Host: " + URLParser(url).getHost() + '<br>');
document.write("Path: " + URLParser(url).getPath() + '<br>');
document.write("Query: " + URLParser(url).getQuery() + '<br>');
document.write("Hash: " + URLParser(url).getHash() + '<br>');
document.write("Params Array: " + URLParser(url).getParams() + '<br>');
document.write("Param: " + URLParser(url).getParam('myparam1') + '<br>');
document.write("Has Param: " + URLParser(url).hasParam('myparam1') + '<br>');

document.write(url + '<br>');

// Remove the first parameter
url = URLParser(url).removeParam('myparam1');
document.write(url + ' - Remove the first parameter<br>');

// Add a third parameter
url = URLParser(url).setParam('myparam3',3);
document.write(url + ' - Add a third parameter<br>');

// Remove the second parameter
url = URLParser(url).removeParam('myparam2');
document.write(url + ' - Remove the second parameter<br>');

// Add a hash
url = URLParser(url).setHash('newhash');
document.write(url + ' - Set Hash<br>');

// Remove the last parameter
url = URLParser(url).removeParam('myparam3');
document.write(url + ' - Remove the last parameter<br>');

// Remove a parameter that doesn't exist
url = URLParser(url).removeParam('myparam3');
document.write(url + ' - Remove a parameter that doesn\"t exist<br>');