I am developing an ASP.NET application that takes user input and serializes them into a text file. Now, when a second update request comes while the file is still being written, an IOException will be generated.How do I handle concurrent update request to this file?
View 2 RepliesIn my website I have configured the following in the web.config
[Code]....
Following is a line in my HttpHandler
[Code]....
Issue is that I cannot see anything written in the file. File gets created but nothing is written in it.
ASP.net radiobutton change event writes the new selection to an XML file and that needs to be shown on the page but does not show the changes on the page since the page load occur before the event fires. give some insight how to resolve this.
View 2 RepliesTHE CODE:
Session["foo"] = "bar";
Response.Redirect("foo.aspx");
THE PROBLEM:
When foo.aspx reads "foo" from the session, it's not there. The session is there, but there's no value for "foo".
I've observed this intermittently in our production environment. But I don't mean here to ask a question about Response.Redirect().
THE EXPLANATION:
Bertrand Le Roy explains (the bolding is mine): Now, what Redirect does is to send a special header to the client so that it asks the server for a different page than the one it was waiting for. Server-side, after sending this header, Redirect ends the response. This is a very violent thing to do. Response.End actually stops the execution of the page wherever it is using a ThreadAbortException. What
happens really here is that the session token gets lost in the battle. My takeaway there is that Response.Redirect() can be heavy-handed
with ending threads. And that can threaten my session writes if they occur too near that heavy-handedness.
THE QUESTION:
What about ASP.NET session management makes it so vulnerable to this? The Response.Redirect() line of code doesn't begin its execution until the session write line is "finished" -- how can it be such a threat to my session write? What about the session write doesn't "finish" before the next line of code executes? Are there other scenarios in which session writes are similarly (as though they never occurred) lost?
In my new job, they have already written an httphandler to handle all the .aspx files, and they are not using asp.net's httphandler. Now, I want to use asp.net's regular .aspx httphandler for some web pages (.aspx files) in the project and the other pages need to be handled using their customized httphandler, i.e., 2 httphandlers for same file type (.aspx), how to do this?
View 1 RepliesOne of the current projects I'm working on is converting an existing Access front end to a web app for a SQL Database. I wasn't involved in the original design of the, formerly, Access db and front end. I have the project nearly complete except for one remaining task, which involved links to part datasheets for a particular part.
The current db has a table with 8 columns "File1" through "File8". For each datasheet created for the part one of these columns is populated with the UNC path to the file, "<Server><Department>Documents<filename>.pdf". The Documents folder currently has over 16000 files stored there. The Access front end has a series of textboxes with associated file save, file open, and delete buttons for each. I could do the same think in the webform where I need to allow access but it doesn't seem very clean.
I've thought about importing the documents to the SQL db then use a fileupload method to maintain them, which I've used in apps for new databases but that seems like a daunting task with the existing db.
Any way to use the existing file path data in the db and existing document folder to allow access to the documents and the user to manage them?
I get this error while trying to run my project: "Column name 'UserID' appears more than once in the result column list." Indeed, the query generated in my SqlTableProfileProvider.vb is the following (text in brackets [] has been changed):
"IF EXISTS (SELECT 1 FROM [table] WHERE UserId = @UserId) BEGIN UPDATE [table] SET UserID=@Value0, LastUpdatedDate=@LastUpdatedDate WHERE UserId = '[Guid]'END ELSE BEGIN INSERT [table] (UserId, UserID, LastUpdatedDate ) VALUES ('[Guid]', @Value0,
@LastUpdatedDate) END"
I'll emphasize that the above statement is generated in SqlTableProfileProvider.vb, which was written by .Net people. While I have little control over its source, I've apparently given the fodder whereby the mistake can be generated. Any clues as to why UserID is being written twice in the statement?
i want to search a text in the database even if user writes wrong spelling.
I am using LIKE operator. But I am not getting exact result.
For example: I want to search 'Norrebro' if user types 'Norebro' (wrong spelling)
LIKE operator does not work in this case. So how can I get the exact result??
I'm using a HttpHandler to intercept PDF file download requests and modify the PDF file. I'm stuck on what to do if the requested file doesn't exist on the webserver. If I handle the Exception and return an empty response, it gives the user a 0 byte file to download. If I ignore the Exception, then ASP.NET catches it and the user is redirected to my unfriendly customError page.
View 9 RepliesAssumptions: Microsoft stack (ASP.NET; SQL Server).
Some content management systems handle user-generated content (images, file attachments) by storing it in the file system. Others store these items in the back end database.
Some examples of both:
[code]....
What's the best approach, and why? What are the pros and cons of keeping user files in the database? Is there another approach?
I have set up the maxRequestLength :-
<httpRuntime
maxRequestLength="10000"/>
Then I found this solution online to handle the error if someone tries to upload file bigger than 10 MB
[Code]....
This works great on my local machine but when I try to run it from Production server , It still shows me the "Internet Expolrer cannot display webpage". I just want to display a nice message to user when He tries to upload file larger than 10 MB.
Using C# .NET 3.5 with VS 2008.
I've been playing with the FileUpload control for an upcoming project where the user is allowed to upload up to five files at once, but each file can only be 5MB in size. Simple enough all I would need to do is add in the httpRuntime element to the web.config and up the file size and timeout.
[Code]....
what I'm really getting at is there a better way to trap if the file size is too large before processing while using the FileUpload control. I would like to be able to keep the user on the same page but update a label control.
I have a website that contains several aspx pages linked to a single aspx.vb code behind file. Four of these aspx pages have a single button on each (four total). My issue is handling each button's click event on each page using the single code behind file.
My four buttons' names are:
[code]....
not quite sure where I'm going wrong here. I'm trying to manually handle sorting in a Gridview that is populated with the following data source:
[Code]....
[Code]....
[Code]....
At the moment, nothing is happening when I click on the column headings. I ran it in debugging mode in Visual Studio and put a breakpoint on the Sorting event handler. I noticed that the variable dtSortTable is empty even after the TryCast(VacanciesGV.DataSource, DataTable). If I hover over this statement in debugging, it shows the data from the file system, so it does appear to be reading it.
I am working in a school and we recently installed a new server running WinServer 2008R2. I want to be able to point people to a URL on our intranet and have them fill out a simple registration form and have this data written to a database. It would also be nice to have some data auto-populate (such as their name).
Is it overkill to set up a sharepoint server and try to do this with Access Webforms? Could I use something like dotnetnuke and find a module that works? Or how about options for writing custom forms?
I am a windows application developer doing a web application with VB.net and SQL 2008 for the first time.I have developed a web application where users are supposed to view a file after selecting from a listbox. I then pick the users logon ID from windows then store in database and produce statistical reports later. It was working fine on my local machine till i deployed it on server to make it accessible on the intranet. The server OS is Windows 2008 Server and runs IIS. My issues are as follows,1. The application is unable to store the user logon id from the client.2. When more than one user uses the application, then there are errors but one user does not produce errors.
View 1 Replieswe are using the WCF service and hosted using a console application, now we are using LoadRunner and hitting it concurrently
Where giving 50 hits at a time few requests (26) gets completed successfully and remaining gives error TCP error code 10061: No connection could be made because the target machine actively refused it.
I am a windows application developer doing a web application with VB.net and SQL 2008 for the first time.
I have developed a web application where users are supposed to view a file after selecting from a listbox. I then pick the users logon ID from windows then store in database and produce statistical reports later. It was working fine on my local machine till i deployed it on server to make it accessible on the intranet. The server OS is Windows 2008 Server and runs IIS. My issues are as follows,
1. The application is unable to store the user logon id from the client.
2. When more than one user uses the application, then there are errors but one user does not produce errors.
I am working on a website in which more than a thousand users can login at a time and there may be more than 50000 total users. I am worried about the performance of the application in case of concurrent access.
what is the best way to manage that, so that my application runs without any performance issues.
in one request i am updating session variable. in the other request, i am trying to access that session value, but it was blocked until the first request finish. I am using C# with ASP.NET 2.0 UPDATE: My page code looks like this.
while(int progress = DoWork() && progress <= 100 ){
Session["Progress"] = progress;
}
and my handler just return Session value.
context.Response.Write(Session["progress"].toString());
context.Response.End();
Can I call a PageMethod and then call another PageMethod before the first has finished? Are concurrent calls to PageMethods allowed?
View 1 RepliesI want to prevent concurrent login under same username. I am using aspnet_users & membership concepts. So How can I achieve this....
View 6 Repliesconcerning requests being blocked from a main window after a popup window had initiated a file download. Further requests from the same session are being queued until the download is complete. So, is there any way to override this? Is there anyway to tell asp.net to not serialize same session requests? Is there any way to tell asp.net to ignore session for a specific request...httphander(module) or otherwise?
why requests from the same session are being queued until the download is complete. please tell me the funda behind it and how to overcome it.
I'm developing web application with concurrent user using the application. The problem i'm facing is that if the first user login his details are taken affecting the second user how is process the data in the application.How to avoid it?the best way to code to maintain concurrent users.
View 4 RepliesI'm having an issue with my hosting provider (winhost.com). My app is built on ASP.NET 4 MVC 3. Up until a few days ago, everything was running fine. All of a sudden I've started getting 503 errors when trying to access my site (wikipediamaze.com). It doesn't happen all the time, just most of the time.
When someone starts playing the game a request is made to wikipedia.org to get the contents of the page for the current step in the puzzle. Basically I'm screen scraping wikipedia.org, injecting some html and then displaying the results. All of my web requests are closed immediately after receiving the data.
What winhost is telling me is that there are connections remaining open and causing any additional requests to the site to get the 503 Service Unavailable Error. What I can see from my end is that only 1 request is ever allowed to be made to wikipediamaze.com at a time. If you keep refreshing the page you'll eventually get the HTML but all subsequent requests (css,images,js) all get the 503 error. Even pages that don't ever call out to wikipedia.org.
If it was an issue with connection throttling in IIS, do both incoming and outgoing (requests made internally) fall in to the same bucket? If I'm sure all of my connections are being closed (and I've never had this issue before) what else could cause this?