JS 获取URL地址参数

　　/**
     * [通过参数名获取url中的参数值]
     * 示例URL:https://www.baidu.com?open=yes
     * @param  {[string]} pName [参数名]
     * @return {[string]}           [参数值]
     */
    function GetQueryValue(pName) {
        var query = decodeURI(window.location.search.substring(1));
        var vars = query.split("&");
        for (var i = 0; i < vars.length; i++) {
            var pair = vars[i].split("=");
            if (pair[0] == pName) {
                return pair[1];
            }
        }
        return null;
    }
    var open = GetQueryValue('open');
    console.log(open)    // yes