给url额外添加参数

patchUrlParams.js

/**
 * 给url额外添加参数
 * @param url
 * @param {object} params 要添加的参数
 * @returns {*|Element}
 */
function patchUrlParams (url, params) {
    var a       = document.createElement('a');
    var _params = {};

    a.href = url;

    // 提取参数
    if (a.search) {
        var searchStr = a.search.slice(1).split('&');

        while (searchStr.length) {
            var param = searchStr.splice(0, 1)[0];

            _params[param.split('=')[0]] = param.split('=')[1];
        }
    }

    // 继承参数
    for (var p in params) {
        if (!params.hasOwnProperty(p)) continue;

        _params[p] = params[p];
    }

    // 设置参数
    a.search = '';
    for (var p in _params) {
        if (!_params.hasOwnProperty(p)) continue;

        if (_params[p] == undefined) {
            _params[p] = '';
        }

        a.search = a.search += ('&' + p + '=' + _params[p]);
    }

    a.search = a.search.slice(2);

    return a;
}