Object reference not set to an instance of an object. (未将对象引用到实例)

Question

在将对象序列化的时候，本地测试没问题。在iis6下就出现Object reference not set to an instance of an object. 请大虾们帮忙看看.

代码如下:

protected void btnsubmit_Click(object sender, EventArgs e)
        {

            Jisuangongshi jisuangongs = new Jisuangongshi();

            jisuangongs.Zbgs = txtzb.Text;
            jisuangongs.Djgs = txtdj.Text;
            jisuangongs.Jbgs = txtjb.Text;

            save(jisuangongs);
        }

        public void save(Jisuangongshi lstjsuan)
        {
            FileStream filestream = null;
            try
            {
               
                filestream = new FileStream("ProduceCheck.files", FileMode.Create);
                BinaryFormatter bf = new BinaryFormatter();
                bf.Serialize(filestream, lstjsuan);
            }
            catch (Exception ex)
            {
               
            }
            finally
            {
                filestream.Close();
            }
           
            Response.Write("<script>alert('修改成功!');window.location.href='ParaManager.aspx';</script>");
        }

[Serializable]
    public class Jisuangongshi
    {
        private string _djgs;

        public string Djgs
        {
            get { return _djgs; }
            set { _djgs = value; }
        }

        private string _zbgs;

        public string Zbgs
        {
            get { return _zbgs; }
            set { _zbgs = value; }
        }

        private string _jbgs;

        public string Jbgs
        {
            get { return _jbgs; }
            set { _jbgs = value; }
        }

Answer 1

filestream = new FileStream("ProduceCheck.files", FileMode.Create); 这里创建 FileStream 的时候抛出了异常, 你把异常吃掉了, catch (Exception ex) {      throw ex; // 这里出现的异常会告诉你你无权县创建FileStream,或者  ProduceCheck.files 已存在等错误.} 所以,异常会从这里抛出,因为 filestream == null,系统报告 NullReferenceException. finally {                filestream.Close();}

Answer 2

至少说明哪一行报的错啊

Answer 3

 遇到过一种情况是dll 和aspx页面不匹配造成的