How can I add or update a query string parameter?

Question

With javascript how can I add a query string parameter to the url if not present or if it present, update the current value? I am using jquery for my client side development

Answer 1

Code that appends a list of parameters to an existing url using ES6 and jQuery:

class UrlBuilder {
    static appendParametersToUrl(baseUrl, listOfParams) {

        if (jQuery.isEmptyObject(listOfParams)) {
            return baseUrl;
        }

        const newParams = jQuery.param(listOfParams);

        let partsWithHash = baseUrl.split('#');
        let partsWithParams = partsWithHash[0].split('?');

        let previousParams = '?' + ((partsWithParams.length === 2) ? partsWithParams[1] + '&' : '');
        let previousHash = (partsWithHash.length === 2) ? '#' + partsWithHash[1] : '';

        return partsWithParams[0] + previousParams + newParams + previousHash;
    }
}

Where listOfParams is like

const listOfParams = {
    'name_1': 'value_1',
    'name_2': 'value_2',
    'name_N': 'value_N',
};

Example of Usage:

    UrlBuilder.appendParametersToUrl(urlBase, listOfParams);

Fast tests:

    url = 'http://hello.world';
    console.log('=> ', UrlParameters.appendParametersToUrl(url, null));
    // Output:  http://hello.world

    url = 'http://hello.world#h1';
    console.log('=> ', UrlParameters.appendParametersToUrl(url, null));
    // Output:  http://hello.world#h1

    url = 'http://hello.world';
    params = {'p1': 'v1', 'p2': 'v2'};
    console.log('=> ', UrlParameters.appendParametersToUrl(url, params));
    // Output: http://hello.world?p1=v1&p2=v2

    url = 'http://hello.world?p0=v0';
    params = {'p1': 'v1', 'p2': 'v2'};
    console.log('=> ', UrlParameters.appendParametersToUrl(url, params));
    // Output: http://hello.world?p0=v0&p1=v1&p2=v2

    url = 'http://hello.world#h1';
    params = {'p1': 'v1', 'p2': 'v2'};
    console.log('=> ', UrlParameters.appendParametersToUrl(url, params));
   // Output: http://hello.world?p1=v1&p2=v2#h1

    url = 'http://hello.world?p0=v0#h1';
    params = {'p1': 'v1', 'p2': 'v2'};
    console.log('=> ', UrlParameters.appendParametersToUrl(url, params));
    // Output: http://hello.world?p0=v0&p1=v1&p2=v2#h1