表单的ajax填入问题

       //1.判断target.value是以modify开头的还是delete开头的
        //2.若以modify开头，则可以获得account
        //3. 处理modify的情形
        var node = target.parentNode.parentNode;
        strCode = target.value;
        var fdStart = strCode.indexOf("modify");
        var fbStart = strCode.indexOf("delete");
        var flStart = strCode.indexOf("result");
        var evId = node.childNodes[2].innerHTML;
        if (fdStart === 0) {

            var uem = new XMLHttpRequest();
            uem.onload = function () {
                if (uem.status === 200) {
                    responseObject = JSON.parse(uem.responseText);
                }
                var newData = "";
                    newData  = ""
                        + ''
                        + ''
                        + ''
                        + '
'+responseObject.events[1].allow_photographer+'
'
                        + ''
                        + "
取消 " +
                        "确定
"
                        + "";

                    document.getElementById("usemf").innerHTML = newData; alert(uem.responseText)
            };
            uem.open("get", "../requests/myEvent/modifyExistingEventByEventCode.php?eventId="+evId+"", true);
            uem.send();
        }