c＃ - asp.net ::会话值在Response.Redirect（Request.Url.AbsoluteUri）后变为null [英] c# - asp.net :: Session Value gets null after Response.Redirect(Request.Url.AbsoluteUri)

问题描述

嘿伙计们，我正在制作一个视频处理程序，我想在我的网页上播放来自数据库的视频。



但是这个网站是基于用户的所以我有会话保持我的信息在页面之间运行。



问题发生在我选择了视频文件后我按上传。在Response.Redirect之后（Request.Url.AbsoluteUri） ）;

所以我得到null异常..

我试图使用Response.Redirect（〜/ Default.aspx？Email =+ PID）;



上传后页面加载好但是我没有播放视频，所以我想是否需要使用absoluteURI来播放视频...



有什么想法吗？这是代码，东西发生在BindGrid（）;和bttnUpload。



谢谢:)

 命名空间 ShowingImages 
 {
  public   partial   class 默认值：System.Web.UI.Page 
 {
 
  public   string  query，constr，query1，query2，query3; 
  public  SqlConnection con，conn; 
  public   void  connection（）
 {
 constr = ConfigurationManager。 ConnectionStrings [  Myconnection]。ToString（）; 
 con =  new  SqlConnection（constr）; 
 con.Open（）; 
} 
 
 
 
 
 受保护  void  Page_Load（ object  sender，EventArgs e）
 {
 Label1.Visible = 假; 
 PID =（ int ）（会话[  ID]）; 
  if （！IsPostBack）
 {
 
 
 
 HttpContext context = HttpContext.Current ; 
 UserProfile objUserProfile = Session [  UserData _ + PID]  as  UserProfile; 
 lblemail.Text = objUserProfile.First_Name; 
 lblname.Text = objUserProfile.Email_Account; 
 
 
 
  if （PID ==  null  ）
 {
 Response.Redirect（  Login.aspx）; 
} 
 
 imagebindGrid（）; 
 PostSelection（）; 
 
} 
} 
 
  private   void  InitializeComponent（）
 {
  throw   new  NotImplementedException（）; 
} 
 
 
 受保护  void 上传（< span class =code-keyword> object  sender，EventArgs e） //  buttonγιατοuploadτης φωτο。 ΚαλειταιηκλασηImageupload（） 
 {
 
 Imageupload（）; 
} 
  / *  Κλασσηγιαuploadεικονας。 Ελεγχοςκαιπερασμαεικονας* /  
  private   void  Imageupload（）
 {
  if （FileUpload1.HasFile）
 {
 PID =（ int ）（会话[  id]）; 
  if （PID！=  null ）
 {
  int  imagefilelenth = FileUpload1.PostedFile.ContentLength; 
  byte  [] imgarray =  new   byte < /跨度> [imagefilelenth]; 
 HttpPostedFile image = FileUpload1.PostedFile; 
 image.InputStream.Read（imgarray， 0 ，imagefilelenth）; 
 connection（）; 
 query =  插入ImageToDB（user_id，ImageName，Image）值（@ user_id，@ Name，@图像）; 
 SqlCommand com =  new  SqlCommand（query，con）; 
 com.Parameters.AddWithValue（  @ Name，SqlDbType.VarChar）.Value = TextBox1.Text; 
 com.Parameters.AddWithValue（  @ Image，SqlDbType.Image）.Value = imgarray; 
 com.Parameters.AddWithValue（  @ user_id，PID）; 
 com.ExecuteNonQuery（）; 
 Label1.Visible =  true ; 
 Label1.Text =  图像已成功上传; 
 imagebindGrid（）; 
 BindGrid（）; 
 
} 
} 
} 
 
 
 
  / *  Gridviewγιαεικονες* /  
  public   void  imagebindGrid（）
 {
 connection（）; 
 
  //   SQL注入预防！ 
 query =   SELECT id，ImageName，ImageToDB中的图像，其中user_id =（@ PerID）; 
 SqlCommand com =  new  SqlCommand（query，con）; 
 com.Parameters.Add（ new  SqlParameter（  PerID，PID））; 
  //   com.ExecuteReader（）;  
 SqlDataReader dr = com.ExecuteReader （）; 
 dr.Read（）; 
 
 
 Image1.ImageUrl =   Handler1.ashx？id_Image = + PID; 
 
} 
 
  / *  退出按钮* /  
 受保护  void  Button1_Click（ object  sender，EventArgs e）
 {
 
 System.Web.Security.FormsAuthentication.SignOut（）; 
 Session.Clear（）; 
 Session.RemoveAll（）; 
 Session.Abandon（）; 
 Response.Cache.SetExpires（DateTime.UtcNow.AddMinutes（-1））; 
 Response.Cache.SetCacheability（HttpCacheability.NoCache）; 
 Response.Cache.SetNoStore（）; 
 HttpContext.Current.Response.AddHeader（  Cache-Control，  no-cache，no-store，must-revalidate）; 
 HttpContext.Current.Response.AddHeader（  Pragma，  no-cache）; 
 HttpContext.Current.Response.AddHeader（  Expires，  0）; 
 FormsAuthentication.SignOut（）; 
 HttpContext.Current.User =  new  GenericPrincipal（ new  GenericIdentity（ string  .Empty）， null ）; 
 Response.Redirect（ 〜/ Logout.aspx）; 
} 
  / *  ΚλασσηγιατοPost* /  
 < span class =code-keyword> private   void  Txt（）
 {
 
 
 
 尝试 
 {
 PID =（ int ）（会话[< span class =code-string>  id]）; 
  if （PID！=  null ）
 {
 connection（ ）; 
 query1 =  插入Posttext（user_id，Posttext）值（@ user_id，@ Your_Post）; 
 SqlCommand com2 =  new  SqlCommand（query1，con）; 
 com2.Parameters.AddWithValue（  @ Your_Post，SqlDbType.VarChar）.Value = PostBox.Text; 
 com2.Parameters.AddWithValue（  @ user_id，PID）; 
 com2.ExecuteNonQuery（）; 
 lbluser.Text = PostBox.Text; 
 PostSelection（）; 
} 
 
} 
 
 
 
  catch （例外情况）
 {
  //   con.Close（）;  
} 
 
} 
  / *  Κανει选择τακειμενακαιταανεβαζειαποτηνβασηστο网格* /  
  private   void  BindGrid（）
 {
  string  strConnString = ConfigurationManager.ConnectionStrings [  Myconnection ]的ConnectionString。 
 使用（SqlConnection con =  new  SqlConnection（strConnString））
 {
 使用（SqlCommand cmd =  new  SqlCommand（））
 {
 cmd .CommandText =   select * tblFiles; 
 cmd.Connection = con; 
 con.Open（）; 
 DataList1.DataSource = cmd.ExecuteReader（）; 
 DataList1.DataBind（）; 
 con.Close（）; 
} 
} 
} 
 
 受保护  void  btnUpload_Click（ object  sender，EventArgs e）
 {
  using （ BinaryReader br =  new  BinaryReader（FileUpload1.PostedFile.InputStream））
 {
  byte  [] bytes = br.ReadBytes（（ int ）FileUpload1.PostedFile.InputStream.Length）; 
  string  strConnString = ConfigurationManager.ConnectionStrings [  MyConnection的]的ConnectionString。 
 使用（SqlConnection con =  new  SqlConnection（strConnString））
 {
 使用（SqlCommand cmd =  new  SqlCommand（））
 {
 cmd .CommandText =  插入到tblFiles（Name，ContentType，Data）值（@ Name，@ ContentType，@ Data） ; 
 cmd.Parameters.AddWithValue（  @ Name，Path.GetFileName（FileUpload1.PostedFile） 。文件名））; 
 cmd.Parameters.AddWithValue（  @ ContentType，  video / mp4）; 
 cmd.Parameters.AddWithValue（  @ Data，bytes）; 
 cmd.Connection = con; 
 con.Open（）; 
 cmd.ExecuteNonQuery（）; 
 con.Close（）; 
} 
} 
} 
 Response.Redirect（Request.Url.AbsoluteUri）; 
  //   Response.Redirect（〜/ Default.aspx？Email =+ PID）;  
} 
 
 
  public   void  PostSelection （）
 {
 connection（）; 
 
  //   SQL注入预防!!!!  
 query2 =  从Posttext中选择Posttext，其中user_id =（@ PerID）; 
 SqlCommand com1 =  new  SqlCommand（query2，con）; 
 com1.Parameters.Add（ new  SqlParameter（  PerID，PID））; 
 
 
 SqlDataReader Read = com1.ExecuteReader（）; 
 grdemployee7.DataSource = Read; 
 grdemployee7.DataBind（）; 
 Read.Close（）; 
 
} 
  / *  ΚαλειταιηTxt（）γιαναγινειτοPost* /  
 受保护  void  Button2_Click（ object  sender，EventArgs e）
 {
 Txt（）; 
} 
 
  public   string  USER_PID {获得;  set ; } 
  public  DateTime _myid { get ;  set ; } 
 
  / *   --------------- -----Κουμπιγια搜索PROFILE ----------------------------------- * /  
  public   void  Button3_Click1（ object  sender，EventArgs e）
 {
 Response.Redirect（ 〜/ WebForm7.aspx ）; 
} 
 
 
  public   int  PID {< span class =code-keyword> get ;  set ; } 
 
  protected   void  PostBox_TextChanged（ object  sender，EventArgs e）
 {
 
} 
 
  public   string  sqlquer { get ;  set ; } 
 
  public   object  SqlQueryIn {获得;  set ; } 
 
 受保护  void  Button4_Click（对象发​​件人，EventArgs e）
 {
 
} 
} 
} 

解决方案

查看MSDN文档：



http://msdn.microsoft.com/en-us/library/a8wa7sdt(v=vs.110).aspx [ ^ ]



将endResponse指定为false参数：



Response.Redirect（url，false）;

hey guys, im making a video handler and i want to play videos on my webpage from DB.

but this site is user based so i have sessions to keep my info running between pages.

The problem occurs when after i've chosen the video file i press upload.After the Response.Redirect(Request.Url.AbsoluteUri);
So i get null exception..
I tried to use Response.Redirect("~/Default.aspx?Email=" + PID);

the page loaded ok after the upload but i didn't have the video playing, so im thinking if absoluteURI is needed for the video to work...

Any ideas? here's the code , stuff happens at BindGrid(); and bttnUpload.

THANKS :)

namespace DisplayingImages
{
    public partial class Default : System.Web.UI.Page
    {

        public string query, constr, query1, query2, query3;
        public SqlConnection con, conn;
        public void connection()
        {
            constr = ConfigurationManager.ConnectionStrings["Myconnection"].ToString();
            con = new SqlConnection(constr);
            con.Open();
        }




        protected void Page_Load(object sender, EventArgs e)
        {
            Label1.Visible = false;
            PID = (int)(Session["id"]);
            if (!IsPostBack)
            {



                HttpContext context = HttpContext.Current;
                UserProfile objUserProfile = Session["UserData_" + PID] as UserProfile;
                lblemail.Text = objUserProfile.First_Name;
                lblname.Text = objUserProfile.Email_Account;



                if (PID == null)
                {
                    Response.Redirect("Login.aspx");
                }

                imagebindGrid();
                PostSelection();

            }
        }

        private void InitializeComponent()
        {
            throw new NotImplementedException();
        }


        protected void upload(object sender, EventArgs e) // button για το upload της φωτο. Καλειται η κλαση Imageupload()
        {

            Imageupload();
        }
        /* Κλασση για upload εικονας . Ελεγχος και περασμα εικονας */
        private void Imageupload()
        {
            if (FileUpload1.HasFile)
            {
                PID = (int)(Session["id"]);
                if (PID != null)
                {
                    int imagefilelenth = FileUpload1.PostedFile.ContentLength;
                    byte[] imgarray = new byte[imagefilelenth];
                    HttpPostedFile image = FileUpload1.PostedFile;
                    image.InputStream.Read(imgarray, 0, imagefilelenth);
                    connection();
                    query = "Insert into  ImageToDB (user_id,ImageName,Image) values (@user_id,@Name,@Image)";
                    SqlCommand com = new SqlCommand(query, con);
                    com.Parameters.AddWithValue("@Name", SqlDbType.VarChar).Value = TextBox1.Text;
                    com.Parameters.AddWithValue("@Image", SqlDbType.Image).Value = imgarray;
                    com.Parameters.AddWithValue("@user_id", PID);
                    com.ExecuteNonQuery();
                    Label1.Visible = true;
                    Label1.Text = "Image Is Uploaded successfully";
                    imagebindGrid();
                    BindGrid();

                }
            }
        }



        /* Gridview για εικονες */
        public void imagebindGrid()
        {
            connection();

            //SQL Injection Prevention!
            query = "SELECT id,ImageName,Image from ImageToDB where user_id= (@PerID)";
            SqlCommand com = new SqlCommand(query, con);
            com.Parameters.Add(new SqlParameter("PerID", PID));
            // com.ExecuteReader();
            SqlDataReader dr = com.ExecuteReader();
            dr.Read();


            Image1.ImageUrl = "Handler1.ashx?id_Image=" + PID;

        }

        /*Logout Button */
        protected void Button1_Click(object sender, EventArgs e)
        {

            System.Web.Security.FormsAuthentication.SignOut();
            Session.Clear();
            Session.RemoveAll();
            Session.Abandon();
            Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            Response.Cache.SetNoStore();
            HttpContext.Current.Response.AddHeader("Cache-Control", "no-cache, no-store, must-revalidate");
            HttpContext.Current.Response.AddHeader("Pragma", "no-cache");
            HttpContext.Current.Response.AddHeader("Expires", "0");
            FormsAuthentication.SignOut();
            HttpContext.Current.User = new GenericPrincipal(new GenericIdentity(string.Empty), null);
            Response.Redirect("~/Logout.aspx");
        }
        /* Κλασση για το Post */
        private void Txt()
        {



            try
            {
                PID = (int)(Session["id"]);
                if (PID != null)
                {
                    connection();
                    query1 = "Insert into  Posttext (user_id,Posttext) values (@user_id,@Your_Post)";
                    SqlCommand com2 = new SqlCommand(query1, con);
                    com2.Parameters.AddWithValue("@Your_Post", SqlDbType.VarChar).Value = PostBox.Text;
                    com2.Parameters.AddWithValue("@user_id", PID);
                    com2.ExecuteNonQuery();
                    lbluser.Text = PostBox.Text;
                    PostSelection();
                }

            }



            catch (Exception ex)
            {
                //con.Close();
            }

        }
        /* Κανει select τα κειμενα και τα ανεβαζει απο την βαση στο grid */
        private void BindGrid()
        {
            string strConnString = ConfigurationManager.ConnectionStrings["Myconnection"].ConnectionString;
            using (SqlConnection con = new SqlConnection(strConnString))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    cmd.CommandText = "select * tblFiles";
                    cmd.Connection = con;
                    con.Open();
                    DataList1.DataSource = cmd.ExecuteReader();
                    DataList1.DataBind();
                    con.Close();
                }
            }
        }

        protected void btnUpload_Click(object sender, EventArgs e)
        {
            using (BinaryReader br = new BinaryReader(FileUpload1.PostedFile.InputStream))
            {
                byte[] bytes = br.ReadBytes((int)FileUpload1.PostedFile.InputStream.Length);
                string strConnString = ConfigurationManager.ConnectionStrings["Myconnection"].ConnectionString;
                using (SqlConnection con = new SqlConnection(strConnString))
                {
                    using (SqlCommand cmd = new SqlCommand())
                    {
                        cmd.CommandText = "insert into tblFiles(Name, ContentType, Data) values (@Name, @ContentType, @Data)";
                        cmd.Parameters.AddWithValue("@Name", Path.GetFileName(FileUpload1.PostedFile.FileName));
                        cmd.Parameters.AddWithValue("@ContentType", "video/mp4");
                        cmd.Parameters.AddWithValue("@Data", bytes);
                        cmd.Connection = con;
                        con.Open();
                        cmd.ExecuteNonQuery();
                        con.Close();
                    }
                }
            }
            Response.Redirect(Request.Url.AbsoluteUri);
          //  Response.Redirect("~/Default.aspx?Email=" + PID);
        }


        public void PostSelection()
        {
            connection();

            //SQL Injection Prevention!!!!
            query2 = "Select Posttext from Posttext where user_id= (@PerID)";
            SqlCommand com1 = new SqlCommand(query2, con);
            com1.Parameters.Add(new SqlParameter("PerID", PID));


            SqlDataReader Read = com1.ExecuteReader();
            grdemployee7.DataSource = Read;
            grdemployee7.DataBind();
            Read.Close();

        }
        /* Καλειται η Txt() για να γινει το Post */
        protected void Button2_Click(object sender, EventArgs e)
        {
            Txt();
        }

        public string USER_PID { get; set; }
        public DateTime _myid { get; set; }

        /* --------------------Κουμπι για search PROFILE -----------------------------------*/
        public void Button3_Click1(object sender, EventArgs e)
        {
            Response.Redirect("~/WebForm7.aspx");
        }


        public int PID { get; set; }

        protected void PostBox_TextChanged(object sender, EventArgs e)
        {

        }

        public string sqlquer { get; set; }

        public object SqlQueryIn { get; set; }

        protected void Button4_Click(object sender, EventArgs e)
        {

        }
    }
}

解决方案

Look at MSDN documentation:

http://msdn.microsoft.com/en-us/library/a8wa7sdt(v=vs.110).aspx[^]

Specify the endResponse as false parameter:

Response.Redirect(url, false);

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