获取参数

function getUrlParams(name) {
    var url = window.location.search;
    if (url.indexOf('?') == 1) {
        return false;
    }
    url = url.substr(1);
    url = url.split('&');
    var name = name || '';
    var nameres;
    for (var i = 0; i < url.length; i++) {
        var info = url[i].split('=');
        var obj = {};
        obj[info[0]] = decodeURI(info[1]);
        url[i] = obj;
    }
    if (name) {
        for (var i = 0; i < url.length; i++) {
            for (const key in url[i]) {
                if (key == name) {
                    nameres = url[i][key];
                }
            }
        }
    } else {
        nameres = url;
    }
    return nameres;
}

调用： let ifCoupon = getUrlParams("ifCoupon")