我有一个'类'，这是:

function QS(){
    this.qs = {};
    var s = location.search.replace( /^\?|#.*$/g, '' );
    if( s ) {
        var qsParts = s.split('&');
        var i, nv;
        for (i = 0; i < qsParts.length; i++) {
            nv = qsParts[i].split('=');
            this.qs[nv[0]] = nv[1];
        }
    }
}

QS.prototype.add = function( name, value ) {
    if( arguments.length == 1 && arguments[0].constructor == Object ) {
        this.addMany( arguments[0] );
        return;
    }
    this.qs[name] = value;
}

QS.prototype.addMany = function( newValues ) {
    for( nv in newValues ) {
        this.qs[nv] = newValues[nv];
    }
}

QS.prototype.remove = function( name ) {
    if( arguments.length == 1 && arguments[0].constructor == Array ) {
        this.removeMany( arguments[0] );
        return;
    }
    delete this.qs[name];
}

QS.prototype.removeMany = function( deleteNames ) {
    var i;
    for( i = 0; i < deleteNames.length; i++ ) {
        delete this.qs[deleteNames[i]];
    }
}

QS.prototype.getQueryString = function() {
    var nv, q = [];
    for( nv in this.qs ) {
        q[q.length] = nv+'='+this.qs[nv];
    }
    return q.join( '&' );
}

QS.prototype.toString = QS.prototype.getQueryString;

//examples
//instantiation
var qs = new QS;
alert( qs );

//add a sinle name/value
qs.add( 'new', 'true' );
alert( qs );

//add multiple key/values
qs.add( { x: 'X', y: 'Y' } );
alert( qs );

//remove single key
qs.remove( 'new' )
alert( qs );

//remove multiple keys
qs.remove( ['x', 'bogus'] )
alert( qs );

我已经重写了toString方法，所以不需要调用QS::getQueryString，你可以使用QS::toString，或者像我在示例中所做的那样，仅仅依赖于对象被强制转换为字符串。

我喜欢穆罕穆德·法提赫·耶尔达兹的回答，即使他没有回答整个问题。

在他回答的同一行中，我使用了这样的代码:

“它不控制参数的存在，也不改变现有的值。它把你的参数加到最后"

  /** add a parameter at the end of the URL. Manage '?'/'&', but not the existing parameters.
   *  does escape the value (but not the key)
   */
  function addParameterToURL(_url,_key,_value){
      var param = _key+'='+escape(_value);

      var sep = '&';
      if (_url.indexOf('?') < 0) {
        sep = '?';
      } else {
        var lastChar=_url.slice(-1);
        if (lastChar == '&') sep='';
        if (lastChar == '?') sep='';
      }
      _url += sep + param;

      return _url;
  }

测试者:

  /*
  function addParameterToURL_TESTER_sub(_url,key,value){
    //log(_url);
    log(addParameterToURL(_url,key,value));
  }

  function addParameterToURL_TESTER(){
    log('-------------------');
    var _url ='www.google.com';
    addParameterToURL_TESTER_sub(_url,'key','value');
    addParameterToURL_TESTER_sub(_url,'key','Text Value');
    _url ='www.google.com?';
    addParameterToURL_TESTER_sub(_url,'key','value');
    _url ='www.google.com?A=B';
    addParameterToURL_TESTER_sub(_url,'key','value');
    _url ='www.google.com?A=B&';
    addParameterToURL_TESTER_sub(_url,'key','value');
    _url ='www.google.com?A=1&B=2';
    addParameterToURL_TESTER_sub(_url,'key','value');

  }//*/

在URL类中有一个内置函数，你可以使用它来轻松处理查询字符串的键/值参数:

const url = new URL(window.location.href);
// url.searchParams has several function, we just use `set` function
// to set a value, if you just want to append without replacing value
// let use `append` function

url.searchParams.set('key', 'value');

console.log(url.search) // <== '?key=value'

// if window.location.href has already some qs params this `set` function
// modify or append key/value in it

有关searchParams函数的更多信息。

IE不支持URL，请检查兼容性

好的，在这里我比较两个函数，一个由我自己(regExp)和另一个由(annakata)。

将数组:

function insertParam(key, value)
{
    key = escape(key); value = escape(value);

    var kvp = document.location.search.substr(1).split('&');

    var i=kvp.length; var x; while(i--) 
    {
        x = kvp[i].split('=');

        if (x[0]==key)
        {
                x[1] = value;
                kvp[i] = x.join('=');
                break;
        }
    }

    if(i<0) {kvp[kvp.length] = [key,value].join('=');}

    //this will reload the page, it's likely better to store this until finished
    return "&"+kvp.join('&'); 
}

正则表达式的方法:

function addParameter(param, value)
{
    var regexp = new RegExp("(\\?|\\&)" + param + "\\=([^\\&]*)(\\&|$)");
    if (regexp.test(document.location.search)) 
        return (document.location.search.toString().replace(regexp, function(a, b, c, d)
        {
                return (b + param + "=" + value + d);
        }));
    else 
        return document.location.search+ param + "=" + value;
}

测试用例:

time1=(new Date).getTime();
for (var i=0;i<10000;i++)
{
addParameter("test","test");
}
time2=(new Date).getTime();
for (var i=0;i<10000;i++)
{
insertParam("test","test");
}

time3=(new Date).getTime();

console.log((time2-time1)+" "+(time3-time2));

似乎即使使用最简单的解决方案(当regexp只使用test而不输入.replace函数时)，它仍然比分裂要慢…好。Regexp有点慢，但是…喔…

如果你在链接或其他地方弄乱了url，你可能也必须考虑哈希。这里有一个相当容易理解的解决方案。可能不是最快的，因为它使用正则表达式…但在99.999%的情况下，这种差异真的不重要!

function addQueryParam( url, key, val ){
    var parts = url.match(/([^?#]+)(\?[^#]*)?(\#.*)?/);
    var url = parts[1];
    var qs = parts[2] || '';
    var hash = parts[3] || '';

    if ( !qs ) {
        return url + '?' + key + '=' + encodeURIComponent( val ) + hash;
    } else {
        var qs_parts = qs.substr(1).split("&");
        var i;
        for (i=0;i<qs_parts.length;i++) {
            var qs_pair = qs_parts[i].split("=");
            if ( qs_pair[0] == key ){
                qs_parts[ i ] = key + '=' + encodeURIComponent( val );
                break;
            }
        }
        if ( i == qs_parts.length ){
            qs_parts.push( key + '=' + encodeURIComponent( val ) );
        }
        return url + '?' + qs_parts.join('&') + hash;
    }
}

以下几点:

合并重复的查询字符串参数 使用绝对和相对url 在浏览器和节点中工作

/**
 * Adds query params to existing URLs (inc merging duplicates)
 * @param {string} url - src URL to modify
 * @param {object} params - key/value object of params to add
 * @returns {string} modified URL
 */
function addQueryParamsToUrl(url, params) {

    // if URL is relative, we'll need to add a fake base
    var fakeBase = !url.startsWith('http') ? 'http://fake-base.com' : undefined;
    var modifiedUrl = new URL(url || '', fakeBase);

    // add/update params
    Object.keys(params).forEach(function(key) {
        if (modifiedUrl.searchParams.has(key)) {
            modifiedUrl.searchParams.set(key, params[key]);
        }
        else {
            modifiedUrl.searchParams.append(key, params[key]);
        }
    });

    // return as string (remove fake base if present)
    return modifiedUrl.toString().replace(fakeBase, '');
}

例子:

// returns /guides?tag=api
addQueryParamsToUrl('/guides?tag=hardware', { tag:'api' })

// returns https://orcascan.com/guides?tag=api
addQueryParamsToUrl('https://orcascan.com/guides?tag=hardware', { tag: 'api' })