我添加我的解决方案，因为它支持相对url除了绝对url。在其他方面，它与顶部的答案相同，后者也使用Web API。

/**
 * updates a relative or absolute
 * by setting the search query with
 * the passed key and value.
 */
export const setQueryParam = (url, key, value) => {
  const dummyBaseUrl = 'https://dummy-base-url.com';
  const result = new URL(url, dummyBaseUrl);
  result.searchParams.set(key, value);
  return result.toString().replace(dummyBaseUrl, '');
};

还有人开玩笑说:

// some jest tests
describe('setQueryParams', () => {
  it('sets param on relative url with base path', () => {
    // act
    const actual = setQueryParam(
      '/', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('/?ref=some-value');
  });
  it('sets param on relative url with no path', () => {
    // act
    const actual = setQueryParam(
      '', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('/?ref=some-value');
  });
  it('sets param on relative url with some path', () => {
    // act
    const actual = setQueryParam(
      '/some-path', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('/some-path?ref=some-value');
  });
  it('overwrites existing param', () => {
    // act
    const actual = setQueryParam(
      '/?ref=prev-value', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('/?ref=some-value');
  });
  it('sets param while another param exists', () => {
    // act
    const actual = setQueryParam(
      '/?other-param=other-value', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('/?other-param=other-value&ref=some-value');
  });
  it('honors existing base url', () => {
    // act
    const actual = setQueryParam(
      'https://base.com', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('https://base.com/?ref=some-value');
  });
  it('honors existing base url with some path', () => {
    // act
    const actual = setQueryParam(
      'https://base.com/some-path', 'ref', 'some-value',
    );
    // assert
    expect(actual).toEqual('https://base.com/some-path?ref=some-value');
  });
});

最简单的解决方案，工作，如果你已经有一个标签或没有，并自动删除它，所以它不会一直添加相等的标签，有乐趣

function changeURL(tag)
{
if(window.location.href.indexOf("?") > -1) {
    if(window.location.href.indexOf("&"+tag) > -1){

        var url = window.location.href.replace("&"+tag,"")+"&"+tag;
    }
    else
    {
        var url = window.location.href+"&"+tag;
    }
}else{
    if(window.location.href.indexOf("?"+tag) > -1){

        var url = window.location.href.replace("?"+tag,"")+"?"+tag;
    }
    else
    {
        var url = window.location.href+"?"+tag;
    }
}
  window.location = url;
}

THEN

changeURL("i=updated");

试试这个。

// uses the URL class
function setParam(key, value) {
            let url = new URL(window.document.location);
            let params = new URLSearchParams(url.search.slice(1));

            if (params.has(key)) {
                params.set(key, value);
            }else {
                params.append(key, value);
            }
        }

随着JS的新成就，这里是如何将查询参数添加到URL:

var protocol = window.location.protocol,
    host = '//' + window.location.host,
    path = window.location.pathname,
    query = window.location.search;

var newUrl = protocol + host + path + query + (query ? '&' : '?') + 'param=1';

window.history.pushState({path:newUrl}, '' , newUrl);

还有这种可能性Moziila URLSearchParams.append()

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…

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