自己解决了！

需要实现的效果：用户登录 产生_session[shop_id],添加一条记录，添加记录时获得_session[china_id]=mysql_insert_id()，同时上传图片！

uploadify里接收：

    $shop_id = $_REQUEST['shop_id']; //$_SESSION['shop_id']
    $china_id = $_REQUEST['china_id']; //$_SESSION['china_id']

            function saveChina(){

                $('#china_info_from').form('submit',{
                    url: 'china_info_action.php?action=add',
                    onSubmit: function(){
                        return $(this).form('validate');
                    },
                    success: function(data){
                        eval('data='+data);
                        if (data.success){
                            $.messager.alert(data.title,data.msg,'Info');
                            
                            $('#file_upload').uploadify({
                                'scriptData' : {'shop_id':'<?php echo $_SESSION['shop_id'] ?>','china_id':'<?php echo $_SESSION['china_id'] ?>'}
                            }); 
                            
                            
                            $('#file_upload').uploadifyUpload();
                        } else {
                            $.messager.alert(data.title,data.msg,'error');
                        }
                    }
                });
            }            

登录又同时上传图片，会不会造成登录变得很慢啊。