C# - Async Function Thread.Sleep In Web Application?
Sep 8, 2010
I maintain a ASP.NET web application that causes a user's network connection to reset for several seconds when it executes a procedure. Therefore, the page request times out on the user's end as they never receive the web application's response (the connection dies before it gets the response packet).
To resolve this situation, I was contemplating having the ASP.NET page execute an asynchronous function that incorporates a Thread.Sleep(5000); // sleep for 5 seconds before executing the connection reset This way, the browser has 5 seconds to receive the page's response before their connection resets.
I have concerns with using Thread.Sleep and asynchronous functions in ASP.NET though. I've never attempted to do it before, so I'm unsure of the potential problems it may cause. Does anyone see potential problems with starting an asynchronous thread that contains a Thread.Sleep in an ASP.NET application?
lock (this) { if (!isGoodPassword) Thread.Sleep(2000); } I would expect that this would allow all correct passwords without stalling, but if one user enters a bad password another successful password from a different user would also be blocked. However, the lock doesn't seem to lock across ASP.NET threads.
I want a example of multithreading .i want to use it in a web form not on console.i am using C#.net .and how to use thread.sleep method for a particular thread.
I want to introduce a slight wait during some testing functions, to simulate a server call. Is it sane to use Thread.Sleep(int) to introduce the wait or is there a better method to have the server wait?
Note, I'll be pausing long enough for me to visually see a sufficient lag, even tho I don't expect to see such a delay in the actual app. This is for me to visualize the actual delay that could occur.
I plan on running this both in the VS2010 local debugger webserver and in IIS 7. I'm on .NET 3.5
While passing through code in our project I came across a web method that had this code at the end of it:
thread.sleep(6000); return true;
Now, this was done so the jQuery ajax call from the client gets delayed and the ajax animation will show for a little bit longer. This is very wrong in my eyes. There shouldn't be this kind of connection between UI and server side. If he wants the animation to take longer he can use the setTimeOut function in the client side. Here is my problem: how can I explain to the programmer why this is so wrong? Not just because the client/server thing, but why ever call thread.sleep on a website?
I create a NetworkStream from a TCPClient, I then call BeginRead() followed by Thread.Sleep(60000).
It seems that the BeginRead call back function will only ever occur after Thread.Sleep() has completed. Is this expected behaviour?
What I was expecting was for the call back function to be carried out on a separate thread whenever it was ready and that the Thread.Sleep() on the current thread should have no affect on when/how the call back function runs...
I'm currently creating a VT100 terminal emulator, I wanted to created a method that would allow me to make the emulator sleep until a given string is found in the screen buffer. Initially I was trying to call WaitOne() on the IAsyncResult passed back from BeginRead() if the string was missing (this was to allow more data to pass into the system so that the check could then be carried out again until it was passed), after this failed I tried Thread.Sleep instead of WaitOne() but this blocked my BeginRead call back from firing and I'm now I'm starting to think everything is running from a single thread...
I need to call a function everytime a visitor visits one of my website's page. But I do not want the execution of the function to interfere with the interface between the user and the website i.e. different thread. What is the best way to do that on ASP.Net?
I have a page which has populated a database with a set of information that needs to be processed. This could take a considerable amount of time and I want it to run in the background, mean while I will have my web app display a page with an intermittent meta refresh showing me progress of the records in the DB being processed.
What I think I need to do is start an executable, in a different thread running in the backgound on the server which will run until it is complete, without interfering with other web activity.
Can this be done? Do I start it in a different thread? How can I start the exe in that thread and just leave it to do its work?
I want to remove checked items from checklistbox (winform control) in class file method which i am calling asynchronously using deletegate. but it showing me this error message:-
Cross-thread operation not valid: Control 'checkedListBox1' accessed from a thread other than the thread it was created on.
i have tried invoke required but again got the same error. Sample code is below:
In my website, I want to create a seperate thread for a process which needs to constantly run in background. I want to use threading so that my website performance is not degraded.
I want to create thread for following code.
[WebMethod] public void iterativeFunction() { int count = 0; DateTime date1 = new DateTime(2011,5,31); while (System.DateTime.Compare(System.DateTime.Now,date1)<0) { downloadAndParse(); count++; } }
In my web application (ASP.NET) I have a block of code that uses HttpWebRequest to make a call to a REST service and continue execution. Right now it's taking longer than I would like to complete the full web request. The thing is that what the REST service returns isn't useful. Ideally I would like to send an Async web request to the REST service and then NOT wait for a response. The problem is that I've tried it out using request.BeginGetResponse(New AsyncCallback(AddressOf myFunc), Nothing)
To start an async request and instead of NOT waiting (which I would assume would be the default behavior of an async request) it continuously executes the callback function before executing the next line of code after BeginGetResponse.I'm suspecting that ASP.NET may convert it to a sync request when it's within a web application. I'm led to believe this because there's a IAsyncResult result object that is passed into the callback function and when I examine its CompletedSynchronously property it's always set to true.if it's possible to do an async HttpWebRequest (with no wait) from within an ASP.NET web application or is it always converted to a synchronous request?
Can someone explain me what is is the relationship between App Domain and thread? msdn says "threads are free to cross application domain boundaries; a new thread is not created for each application domain." suppose there is one thread t inside Appdomain a1 .there is an another App domain a2 .thread t can cross to a2 from a1 means it can access a2 memory area If thread can cross the app domain boundaries share the memory space then how application domain isolation is still there?
i want a continously running thread in my web application for sending mail to admin if the logged complaint of the user in not solved by technician within 24 hours.
i am able to send mail to administrator
i just want a watch on database for unsolved issues with timespan of more than 24 hours and inform to administrator about the same
I want to load data to my application domain using a thread so it will be executed at all times. How can I achieve this? I want the thread will start when iis starts and terminate when iis exits.
Note:
I want to do this so I can use disconnected architecture in my asp.net application.
I don't know if it's IIS, ASP.NET or IIS7 related. I take a chance here, if you think I'm in the wrong forum, just tell me which one I should post to.
I have made the smallest demo project to illustrate my problem. You can download the sources
Here
Visual Studio 2008, .NET 3.5, IIS7, Windows 7 Ultimate 32 bits. The IIS Website is configured ONLY for Windows Authentication in an Integreated pipeline app pool (DefaultAppPool).
Here's the problem. I have an Asp.NET MVC 2 application. In an action, I start a thread. The View returns.
The thread is doing it's job... but it needs to access Thread.CurrentPrincipal.Identity.Name
BANG
The worker process of IIS7 stops. I have a window that says: "Visual Studio Just-In-Time Debugger An unhandled exception ('System.Object.DisposedException') occured in w3wp.exe [5524]"
I checked with the debugger and the Thread.CurrentPrincipal.Identity is valid, but the Name property is disposed.
If I put a long wait in the action before it returns the view, then the Thread can do it's job and the Identity.Name is not disposed. So I think the Name gets disposed when the view is returned.
For the sake of the discussion, here's the code that the thread runs (but you can also download the demo project. The link is on top of this post):
I'm new to threading and have used it successfully, but limited. I can spawn a thread and have the main thread reference variables in the spawned thread, but I don't know how to allow the spawned thread to reference (and update) variables in the main thread.
Any example threading code I've seen on the web appears to be WAY more complicated than what I do, so I am unable to understand or integrate into my code.
I want to start a new thread to query a database while my web application continues running. I was under the impression that by using threads I can run the querying process independently while the normal web application page cycle carries on, but I could be wrong.
public class DbAsyncQuery { Dictionary<string, object> serviceResults = new Dictionary<string, object>(); public void UpdateBillingDB() { QueryAllServices(); foreach (KeyValuePair<string, object> p in serviceResults) { IEnumerable results = (IEnumerable)p.Value; IEnumerable<object> sessions = results.Cast<object>(); DbUtil.MakeBillingDBEntry(sessions, p.Key); } } public static string[] servicesToQuery = new string[] // Must go in config file ultimately { "xxx.x.xxx.xx" }; public delegate void Worker(); private Thread worker; public void InitializeThread(Worker wrk) { worker = new Thread(new ThreadStart(wrk)); worker.Start(); } public void InitializeQuery() { Worker worker = QueryAllServices; InitializeThread(worker); } private void QueryAllServices() { Dictionary<string, DateTime> lastEntries = DbUtil.GetLastEntries(); foreach (string ip in servicesToQuery) { string fullServicePath = "http://" + ip + ":800/MyWebService.asmx"; //object[] lastEntry = new object[] { lastEntries[ip] }; object[] lastEntry = new object[] { new DateTime(2011, 1, 1, 0, 0, 0) }; object obj = WebServiceHandler.CallWebService (fullServicePath, "MyWebService", "GetBillingDBEntries", lastEntry); serviceResults.Add(ip, obj); } } }
It seems to basically stall and wait to finish the query before loading the page (which can be thousands of rows, so it takes awhile). I put this in the following section of Global.asax:
This is one of my first web pages, and I'm new to threading. I understand there is a difference between creating your own thread and using the ThreadPool. In this method, I am using my own thread, I think. Not sure if that's the best way. The querying process can be completely independent, and its only going to occur on scheduled intervals (every 8 hours or so). The user doesn't need to have up to the minute data, so it can take awhile. I just don't want the site to wait for it to finish, if that's possible.
I have an asp.net application with a background thread. The thread starts when the application starts and it is gracefully stopped when the application ends. I am running the website on a shared host. Unfortunately sometimes the application does not trigger the Application_End event when it ends. I would think that the threads would be killed anyway, but that's not the case. I currently have 4 threads running in the background. Three from previous times the application started and 1 from the current application session. How can I ensure that the threads are shutdown when the application ends? Is there a way for the threads to check if the application was reset or had been reset? Or is there a way to check for these rogue threads at application startup and kill them?
I want to call an action method when an textbox gets focus to get a description of the model object that field is associated with from a database.
I have this jQuery function:
[code]...
It works fine as far as getting the test text, but the problem is if I set a breakpoint in the action method, I see that it gets called over and over, not just when i change focus in the text boxes...
