Web Forms :: Page Not Rendering Image From Session Variable
Apr 27, 2016
below is .ashx file shows error on If context.Session("photo1") <> "" Then why? I need to display an image on button click that saved in database.
imgHandler.ashx:
Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
If context.Session("photo1") <> "" Then
Dim bytes() As Byte = DirectCast(context.Session("photo1"), [Byte]())
context.Response.Buffer = True
Currently in an .aspx file, I am storing a value (filename that was created in that session) in an hidden text box. When the user clicks on the "Print" labeled Hyperlink control, it opens the file that was stored in the hidden text box control. But when the user goes to different screen (in the same session), I loose the filename value that is stored in the hidden text box control. So I would like to store the filename variable in a session variable. So that if the user leaves this .aspx file and comes back to this .aspx file I can load the value into the hidden text box from the session variable.
I want to show my data in next page with well formated in table.I all ready write code for session which show data in next page.but i want to show it in table format and i also want to comapre in database for a price and show too. this is my code for next page:
[Code]....
this code show me data but as i say iwant it in table format and want to comapare session varibles in database i want to show price accoding that particular product. The Pervious page code:
It is possible to create a session variable on page load just for a particular page/url?
The problem that I have is: The user comes to page 1 and the session variable becomes A, then he opens page 2 in a new tab and the session variable because B on both page 1 and page 2.
So when the user needs the session variable on page 1 it does not work because the variable have changed!
I got a variable of type System.Drawing.Image and need to convert it to a variable of type byte so I can store the image in the database. Can someone show me how to do that in VB.NET code.
IDE: MS Visual Studio 2008 / SQL Server 2005 Express / SQL Server Management Studio Express 2005
Skills: Beginner
Well im trying to make a custom login page(im not using ASP.net Login Control), in Admin.aspx page
UserName and Pasword are entered in textboxes , then Code-Behind file checks the UserName and Pasword against DataBase(it stores the UserName and Pasword) if both are correct Session["IsAuthenticated"] = "true" and then user is redirected to AdminArea.aspx
AdminArea.aspx checks if ( Session["IsAuthenticated"].ToString() == "false" ) then redirect to Error page..
but i get NullReferenceException on AdminArea.aspx because Session["IsAuthenticated"] is null , i dont know why ?
I even tried PreviousPage.Session["IsAuthneticated"] but still got the same error..
I debugged,and found out Admin.aspx saves value in Session["IsAuthenticated"] succesfully but AdminArea.aspx looses the Session["IsAuthenticated"]..so it gets null
My Question is how to retain value in Session["IsAuthenticated"] when page is changed (I want to retrieve value in next page from Session)?
I have used a image handler to display image which works fine... My problem is how can v pass the image using sessions on different pages. I have an image control in master page and fileupload control on the content page.... bt m not able to implement sessions for images as image can't be store to string.
I have a session variable which contains a list of elements. The user defines filters, which are sent to the Database, which fills the object with the elements that match. Then, that list is shown in a table. The code goes something like this:
[Code]....
Inside that page there is a button, which sends the request given the user filters. The Server creates the object and the session variable is assigned a value.
[Code]....
It works when the user sets the filters. However, given that once done it, the session variable has a value, I don't understand why if you navigate to other pages, the table doesn't appear when you return, given that:
1. It works when you perform the query and reload the page
2. The Session variable should be set for the rest of the session
I am working on a web application that is consuming a Dataset returned by a web service. As the application is running I store that Dataset as a session variable to be used over and over again as the user navigates to the different pages that will edit the tables within the dataset. The idea was the user will only have to wait for the data once when the application loads then the application would use the session variable until the user saves the changes they made, when that happens it would pass the edited tables to the service to update the database. Is there problems with this design and the storage of the Dataset and Datatables as a session variable?
I would like to wrap Session variables in a manner similar to that discussed on CodeProject.
[code]....
Here is my question: if I have to access CurrentUser multiple times in the same page, would I get a performance improvement by assigning it to a local variable instead of accessing the wrapping property? Or does the HttpSessionState make sure the object is only deserialized once per request, so that subsequent calls in the same http request don't cost any more?
I have a web application which uses a session variable to store the logged in userid. If no user is logged in, of course this variable will be empty and the contents displayed on my website are meant for guests. If there is a user logged in, the user specific controls/access/links will then be a displayed.
I am now having issues with my hosting where on shared application pool, the worker recycle is triggered every 90 minutes, this will clear sessions causing all my users to be logged out. I opted for a dedicated application pool, which got worse because I am only allocated 50MB memory limit and if this is reached, the worker recycle is triggered and I lose my sessions again. I have tried as much as possible optimization techniques, e.g. dispose where possible, close connections, disable viewstate for static controls etc but my memory per instance keeps building up from page to page without any signs of improvement. I don't use loops nor store huge objects like bitmaps etc but my sessions are now gone even faster than 90 minutes in shared application pool before.
I have considered using SQL Session State but there isn't a simple guide on using this with MySQL. I am getting desperate and considering using a public variable, a string as a replacement to store logged in user id instead of in a session variable. I am pretty sure this will solve my issue with sessions being recycled but are there any negative consequences of doing this? One problem I can think of is if the user closes the browser, the system will never know that the user is now logged out and this public variable should be nothing. In this scenario, will the GC eventually clear this abandoned public variable.
I have a background set of images that is called randomly.It changes each time a user opens a new page and refreshes the same page.Not 100% of what I want.
Ideally I would like a random image to be shown each time a user comes to the site but not on every page.
Is there a way to set the image per the session a users visits the site instead of each page?
Current code
SqlConnection connection = null; connection = new SqlConnection(ConfigurationManager.ConnectionStrings["PSI_DB_1ConnectionString"].ConnectionString.ToString()); connection.Open(); int id = Convert.ToInt32(Request.QueryString["id"]); string SQLquery =""; if (id == 0) { SQLquery = "Select Top 1 ImageData,ImageType from WebBGImages ORDER BY NEWID()"; } else { SQLquery = string.Concat("Select ImageData,ImageType from WebBGImages where ImageID=",id); } SqlCommand Cmd = new SqlCommand(SQLquery, connection); SqlDataReader Dr = Cmd.ExecuteReader(); if (Dr.HasRows) { while (Dr.Read()) { Byte[] bytes = ((Byte[])Dr["ImageData"]); Response.Buffer = true; Response.Charset = ""; Response.ContentType = Dr["ImageType"].ToString(); Response.BinaryWrite(bytes); Response.End(); Response.Cache.SetCacheability(HttpCacheability.NoCache); Response.BinaryWrite(bytes); } } Response.Flush(); Response.End(); Cmd.Dispose(); connection.Close(); connection.Dispose();
What I am dealing with is a collection of data from 3rd party sites, some xml, some thumbnail images already.I essentially have an asp page that uses vb to collected the data and display it with some minor formating in a <div>, I use a literal control and a stringBuilder to put together the html and output it to the literal.
So what I've been trying to do without any luck is have the output dump into a stream, then render the html into an image from that stream.I have looked at most of the links that have been posted in simular threads, and none of those are simular to exactly what I am looking for.
i have a gridview with link button and one field called "ID" i have five values....when i click the link button that row value ill show in next page in textboxes ,txtid, txtage, txtsalary,......... if i click that link button that "Id" values should pass to next page using "SESSION" variable in C#.net
What would be the proper syntax in ASP.NEt 3.5 C# to assign a TextBox value to a temporary or session variable to be manipulated (added, subtracted, multiplied, divided) at different points in the application? I want to add a decimal number to this variable in almost every instance as well.
i want to upload picture throw FileUpload control and then store it in session, after store in session i want to read it out to image control and insert to database.
In my web application, I have to load different Master pages depending on the user log-in information. When I say different, I mean not just the colors but a whole new look[including navigation options]. So I am using 2 Master pages [one of them is set as default] and depending on the user information the other page will be used.
I got it to work by storing the user information in a Session variable and applying the master page dynamically using the Page_PreInit event. But the issue is, if I hit the back button, sometimes [yeah, only sometimes !!!] the master page is reset to the default page. Initially I thought it is a Session timeout issue. But it isn't, as some of the session variables still have data. Can anyone explain whats actually happening?
I have the dataset. in this i am having total 20 tables with huge amount of data..I want use this data over all the page..so where i can keep this data..
before i used viewstate but the viewstate data is render to page every postback ..so this time the page size is increasing(interanlly viewstate is rendered to page)..so performence wise it was very slow..
Now i change my logic insted of viewstate to i used Globel Dataset on Page Level.. now the performence wise better than viewstate..
i used Like shared dsControls as Dataset at top of the page..so every time i use this dataset..
my quesation is session is better or Globel variable is better way use in my situavation..
