JS 給url添加參數

/** 
* 給url添加參數
* @param key {string} 參數名稱
* @param val {string} 參數值
* @return {string}
*/
function addOrgToUrl(key, val) {
    var url = window.location.href
    if (url.indexOf(key) > -1) {
        var re = eval('/(' + key + '=)([^&]*)/gi');
        url = url.replace(re, key + '=' + val);
    } else {
        var paraStr = key + '=' + val;
        var idx = url.indexOf('?');
        if (idx < 0){
            url += '?';
        }else if (idx >= 0 && idx != url.length - 1){
            url += '&';
        }
        url = url + paraStr;
    }
    return url;
}