Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack

Question

I'm new to this forum. I hope you can help me.

I'm using the Enterprise edition of VS 2005. When I debug my project an exception is raised - 'Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack'. I can't find anything about this on-line. I suspect this message is hiding the true exception. Does anyone know what this message means?

Regards,

Andy Ham

 

Answer 1

Andy,

There are two things that I would check. First, make sure that you are working with a debug build and not a release build of your project. And second, make sure that you are debugging in mixed mode (both managed and native) so that you can see all of the current call stack.

 

Thanks,

Ian

Answer 2

Hi Ian,

Thanks for your help. I can confirm that I was using debug mode anyway, but I'll take your second suggestion into accout, the next time I get this error.

Fortunately, after removing a try-catch block and adding a Trace I managed to get the code working again. I'm still not sure what the cause of the original problem was, but at least I can continue now. Thanks again!

Regards,

Andy

 

Answer 3

Andy,

No problem, glad that I could help. Just come back to these forums if you have any more development issues.

 

Thanks,

Ian

Answer 4

Ian,

I am expressing the same issue.  I can provide a sample code block that shows the issue.  Before I provide the code block, I would like to try your suggestion of debugging in mixed mode (both managed and native) so that I can see all of the current call stack; however, I can figure out where to set the mixed mode debugging.  Where in VS2005 do I set this option?

Thanks,
Jim.

Answer 5

Jim,

Check under the following:

Debug->Attach to Process

In the attach to process dialog hit the "Select..." button and check the boxes for both Native and managed code. Now you will attach in mixed mode for debugging.

 

Thanks,

Ian

Answer 6

Dear Ian,

I have similar problem which showing these unable.. message in the debugging in VS 2005 Team Suite (released).
I had my attached debug module in both Native & Managed code mode, the module I attached to debug is in debug mode ( its the windows service app).
Not having any error (yet!) but unable to look at values of any objects as it's showing this message.
- Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack

Hope you can help me.

Thank you
Punprom Kasemsant

Answer 7

I have a similar problem...here is the code for a 'csv' download. Can someone help?

Response.Clear();

Response.ClearHeaders();

//set the conttent type of the file to be downloaded (IF NEEDED)

Response.ContentType = "application/vnd.ms-excel";

// initialize the http content-disposition header to indicate a file attachment with the filename

Response.AppendHeader("Content-Disposition", "Attachment; Filename=\"" + strFileNameCSV + "\"");

//// transfer the file byte-by-byte to the response object

FileInfo fileToDownload = new FileInfo(strFileNameCSV);

Response.Flush();

Response.WriteFile(fileToDownload.FullName);

Response.End();

Answer 8

Seems to ba a relatively common thing. I am still attempting to figure it out. I have a Dataset that I am using to populate a .CSV file and provide the ability for the end user to 'download' the resulting file. I am populating the dataset and populating a DataTable with it. I am then creating the Folder and File with the extension '.CSV'. I then populate the file row by row using a string. The file is in the correct location, format (.CSV) and properly populated at this point.

I then call a function that I have attempted to allow the user to download the file. I have attempted this in several different fashions using the Response object. All attempts are downloaded without the .CSV extension. I have pasted some of the code to preform this function below. I do trap an error that states "Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack". I have 'Googled' this error and modified my VS Options>Debugging>Just-in-Time to all the Debug in mixed mode (Managed and Native). The error occurs when I step through the code at the Response.End
I have attempted this with the HtmlTextWriter, StringWriter, StreamWriter and StringBuilder all with the same result.

Can someone assist?


string strFileNameCSV = "C:\\ExportReports\\Export_CSV_" + ReportForm1.strUserID + ".csv";
//FileInfo fiBPM_Export = new FileInfo(strFileNameCSV);

//Clear Headers
Response.Clear();
Response.ClearHeaders();

// initialize the http content-disposition header to indicate a file attachment with the filename
Response.AppendHeader("Content-Disposition", "Attachment; Filename=\"" + strFileNameCSV + "\".csv");

////// transfer the file byte-by-byte to the response object
//FileInfo fileToDownload = new FileInfo(strFileNameCSV);
//Response.Flush();
//Response.WriteFile(fileToDownload.FullName);
Response.WriteFile(strFileNameCSV);
//Response.TransmitFile(strFileNameCSV);
//Response.Redirect(strFileNameCSV);
Response.End();

 

Answer 9

I have received the "Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack" but only when I am trying to perform a redirect from within a try catch block. If I move the redirect outside the block it works fine. I created a bool value that was set in the try catch block and then performed an if statement against the bool to perform the redirect. Not my first choice for coding but it solved my problem and allowed me to me on. Good luck.

Answer 10

Ian,

A small correction........it is Tools > Attach to Process instead of  Debug->Attach to Process

 

Thanks

Rajesh Medackel, India

 

 

Answer 11

I believe the answer to your problems are explained here

Answer 12

Thanks!!

I was having the same problem here.. and now it works..

once again. thanks.

Answer 13

Hello,

I am having a similar problem except I am attempting to debug a SQL server 2005 c# assembly remotely.

If I try to set the attach process parameters to use anything but the default "Automatic: T-SQL code, Managed code", then I cannot issue a "Detach All" from within Visual Studio as this is grayed out. I then have to issue a "Terminate All" which forces SQL server 2005 to hang up and I have to restart the SQL server services. In addition, my break points are ignored.

The problems come with trying to access an SQL data reader.  Typical code is as follows:

using (SqlConnection c = new SqlConnection("context connection=true"))

{

SqlCommand cmd = new SqlCommand();

cmd.Connection = c;

cmd.CommandText = "SELECT TestID, TestName, TestTypeID from inserted";

if (c.State != ConnectionState.Open)

c.Open();

SqlDataReader r = cmd.ExecuteReader();

int TestID = 0;

int TestTypeID = 0;

string TestName = "Control";

if (r.HasRows)

{

r.Read();

TestID = int.Parse(r["TestID"].ToString());

TestTypeID = int.Parse(r["TestTypeID"].ToString());

//*********************************

//TODO: ItemName is specific to each table, so make sure it's ok

TestName = r["TestName"].ToString();

}

r.Close();

}

On trying to assign to the variables, from the reader, the values of the items of the reader, r, are replaced with the "Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack" and the debugger exits at that point.

Any ideas

Thanks

William  

Answer 14

Func-eval (property evaluation) is evil.

What the error means is that the thread is currently stopped in either (a) optimized code or (b) in native code (really, anywhere outside of code that was not directly generated from IL ).

For a) switching to debug-mode will help. However, if you've stopped in a 3rd-party dll (or the FX), that code may still be optimized even if your project's code is debug. Hitting Break at when a System.Diagnostics.Debug.Assert fires is an example of this. The code that implements Debug.Assert is in a separate library (system.dll) which is optimized even if the rest of your solution is non-optimized.

In this case, the intersting thing is to get a callstack of where the thread is. The real problem may be that the thread shouldn't even be stopped there in the first place.

For b) func-eval can only be initiated in code that was jitted from IL. So you can't initiate a func-eval of a managed method if your thread is outside of managed code.  There are further restrictions too (some listed here)

 

 

More gory technical details are here:

http://blogs.msdn.com/jmstall/archive/2005/11/15/funceval_rules.aspx

Answer 15

Hi Mike,

Many thanks for the information provided. If I do not run the debugger then all is fine and well. So the question is; How does one access, in my case, the information in the "inserted" table?  If I cannot use property getters then I am truly stumped.

The link provided indicated that r["somecolumn"].ToString() was an invitation to trouble. So you can see the pickle I'm in in that there doesn't seem to be a way of accessing the "inserted" table without falling foul of func-eval(property evaluation).

Kind regards

William

Answer 16

 

I am also experiencing this problem. However, it only happens when the screen is being idle for some amount of time. I have no idea why the response.redirect statement causing that error. It works fine as long as the application is constanly being used. The error goes away after I remove the try and catch blocks but then I encounter a new problem with the statement below:

sUserId = new Guid(Session["QAUSERID"].ToString()); 

The new error arises because the session variable above is null. For some reason when the screen is being idle, the session variable's value is gone.

Hope someone can help me. Thanks in advance.

blumonde

Answer 17

Hi,
I also encountered the same problem.
When Response.Redirect is moved from try block to finally block it worked .

Regards,
Nishant Sharma

Answer 18

I tried the workaround (using HttpContext.Current.ApplicationInstance.CompleteRequest(); to replace  //HttpContext.Current.Response.End();)and it gives me "Unable to read file" message.

 

 

Answer 19

Thanks Nishant.

I moved

HttpContext.Current.Response.End();

to the finally block and it works perfectly.

(NOTE: http://support.microsoft.com/kb/312629/EN-US/ not working for me and gives error of "Unable to read file")

David

 

Answer 20

I faced same problem but could resolve it when I moved REsponse.Redirect outside try catch block.

Similarly it is the same for

HttpContext.Current.Response.End();

or response.end

For any clarification contact me.

Answer 21

I too got rid of this error by moving the response.redirect statements into finally block.

Is it a bug with VS2005?  because i am not able to get the reason why it is coming.

 

 

 

Answer 22

I really didn't have the rime to read all the responces so what i will say might have been said before..

but the solution is to add another boolian parametar.

i mean your code should be like Resoponce.Redirect("Page.aspx", false);

Hope this could help

Answer 23

Instead of this:
try
{
    string someUrl = "http://www.microsoft.com";
    Response.Redirect(someUrl);
}
catch
{}

Try this approach instead:
try
{
    string someUrl = "http://www.microsoft.com";
    Response.Redirect(someUrl, false);
}
catch
{}

This allows the current thread to exit gracefully and not die immediately.

Answer 24

Hello Shawn O,

You need to add this line

Response.ContentType = "application/octet-stream"

Before this line

Response.AppendHeader("Content-Disposition", "Attachment; Filename=\"" + strFileNameCSV + "\".csv");

 

 

 

 

Answer 25

Hi,

I was also having same problem, but now it is solved.

Thanks

Shital

Answer 26

I was comming accross the same problem , but this did work for me, Thank You very Much

Response.Redirect ("nextpage.aspx", false);

Answer 27

Hi Shaddix,

 

Thanks for giving the right link.

 

Thanks again.

 

Thanks

Sushil Jinder

[e-mail]

Answer 28

Hi,

 

   Will this cause to expire the session frequently. Pls help

Answer 29

Hi rajesh,

I am not getting tools>Attach to process as i am also facing the same problem.

Sumit

Answer 30

Hello Andy,

Iam facing the same problem but my scenario is different.

 

when i start my application for the first time, it runs fine. After signout when i signin again, after successfull signin, the system throws the exception when i use response.redirect().

 

i have also noticed that, after signin, when i put any thing in the session variable, i face this problem, else the system works fine, and i need to put the user name and id in the session when the user logs in

 

the other thing which i have noticed is that, when i close the browser window after signout, and signin in a new window, the system works fine.

 

P.S: iam not using asp.net authentication and authorization, and iam also removing all the session variables on signout using session.abandon() and session.clear()

 

Answer 31

 

ok i was also facing the same problem but when i moved to finally block its not throwing any exceptions....

 

 

but why i want to know the reason...can you tell me.....

 

Abinash T

Answer 32

Do one thing. Create a new Ajax enabled web site project.

And copy its web .config file to your web site project.

Add your project related settings there, such as db connection string, impersonate tag etc.

 

Thats it.

And run your website again. You will never see that error again

 

Also you try to use Response.Redirect("") instead of Server.Transfer(""). This may fix the problem.

 

 

Answer 33

Thanks Wes,

 

The link was helpful.

 

Answer 34

cheers Wes (y)

Answer 35

 

Try after puting your Response.Redirect line in finally { ...}

Answer 36

Thanks,

This solved my prob.

Answer 37

Thanks Nishant. I hope this will solve the problem. You can't put Response.Redirect or Response.End in the Try Catch block I guess.

---

Success is where preparation and opportunity meet.

Answer 38

To Debug in Mixed Mode:

http://msdn.microsoft.com/en-us/library/kbaht4dh.aspx

Answer 39

To Debug in Mixed Mode:

http://msdn.microsoft.com/en-us/library/kbaht4dh.aspx

Answer 40

Hi

I have experienced this problem in SharePoint, I also got the 
{Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack.} exception

I had a FormsAuthentication.RedirectFromLoginPage(sDecryptedUsername, true); call that would redirect after a user have logged in. It is as if the code knows that there is another thread spawned, and anything before or after the redirect causes this error. Mine was particularly when I tried to add a new list to the SPWeb

spweb.Lists.Add("Title", "Description", SPListTemplateType.DocumentLibrary);

Answer 41

I was using VS2008. I was having the same problem when having Response.Redirect ("pagename.aspx") within a try block.
Now I used Response.Redirect("pagename.aspx",false). It started working fine

Answer 42

HttpContext.Current.Response.End();
just type in Catch Block and seee probelm will be solved.

Answer 43

I believe the answer to your problems are explained here

Its kind of wierd. I was using server.transfer i never got error. Now I have to add some more things to application and I have got this error. Thanks for posting it. After i changed it to respons.redirect with false i am able to go on.

Answer 44

If you received the error in this thread and you have a Response.Redirect in a try catch, then your best answer for this is from Wes and Jared.  It works to move the Response.Redirect out of the try catch as well, but this is a bit easier.  If you get the error because of something else, then some of the other responses to this thread may help you as well, but for the Response.Redirect in the try catch, this should do it for you.

From Wes Shaddix:

I believe the answer to your problems are explained here

AND

From Jared Turner:

Instead of this:
try
{
    string someUrl = "http://www.microsoft.com";
    Response.Redirect(someUrl);
}
catch
{}

Try this approach instead:
try
{
    string someUrl = "http://www.microsoft.com";
    Response.Redirect(someUrl, false);
}
catch
{}

This allows the current thread to exit gracefully and not die immediately.

Answer 45

I ran into the same situation. See the code below. The issue related to me having my Redirect.Response(HomePageScr.aspx) within my try block of code. For some extenuating reason, once the redirect row was hit, the code fell through into the CATCH block. I simply removed the Response.Redirect("HomePageScr.aspx");
from within the TRY block and things worked according.

protected

 

void SetUpCookieData()

{

 

try

{

 

//Get UserID

userID = GetUserID();

 

//Get User Info

GetUserInfo(userID);

 

//Set User Cookie

 

HttpCookie aCookie = new HttpCookie("userInfo");

aCookie.Value =

Convert.ToString(empTypeID);

 

aCookie.Value("lastVisit") = DateTime.Now.ToString();

Response.Cookies.Add(aCookie);

Response.Redirect("HomePageScr.aspx");

}

 

// LogAccess(UserID);

 

//Call Main Menu

 

}

 

catch (Exception CookieError)

{

 

 

this.lbl_dbError.Visible = true;

 

this.lbl_dbError.Text = CookieError.Message;

 

 

}

 

 

Answer 46

Thanks buehlej


Regards
Rajendra Yerra

Answer 47

"Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack." was my error, as well.

I found that, in addition to the causes at http://support.microsoft.com/kb/312629/EN-US/, as mentioned, that Thread.Abort(); placed after the Thread has already completed also causes this exception.  At least it did for me.  I just removed the line and all was well.

-Tom

Answer 48

Hello

U just add false as a second argument

like

 Response.Redirect(".aspx?ID=" + _ID,false);

 

Thanks

Answer 49

even i m facing the same problem with response.redirect() thing.

following is the code:

	String adPath = "LDAP://bw.com"; //Fully-qualified Domain Name
        LdapAuthentication adAuth = new LdapAuthentication(adPath);
        if (true == adAuth.IsAuthenticated(txtDomain.Text, txtUsername.Text, txtPassword.Text))
        {
            String groups = adAuth.GetGroups();
            //Create the ticket, and add the groups.
            bool isCookiePersistent = chkPersist.Checked;
            FormsAuthenticationTicket authTicket = new FormsAuthenticationTicket(1, txtUsername.Text,
                                                      DateTime.Now, DateTime.Now.AddMinutes(60), isCookiePersistent, groups);
            //Encrypt the ticket.
            String encryptedTicket = FormsAuthentication.Encrypt(authTicket);            
            //Create a cookie, and then add the encrypted ticket to the cookie as data.
            HttpCookie authCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket);
            authCookie.Values["Name"] = txtUsername.Text;

            if (true == isCookiePersistent)
                authCookie.Expires = authTicket.Expiration;
            //Add the cookie to the outgoing cookies collection.
            Response.Cookies.Add(authCookie);
        }
        else
        {
            errorLabel.Text = "Authentication did not succeed. Check user name and password.";
        }
        //You can redirect now.
        Response.Redirect("~/home.aspx", false);

i tried removing the try-catch block but to my surprise it worked fine for first 2-3 logins and then started giving anonymous errors.

like, unable to evaluate the expression or wont give any error but will remain on login page.

i am not able to debug this problem can anyone help me out

where is the error in code?

 

 

Answer 50

 I had this same problem too, and it was tricky. For me, it was because I'm using Ext.Js javascript library. If you are doing a response.redirect in server-side code that you accessed in an Ajax call, there are problems. Ext.js has a workaround with their Ext.Redirect method.

Answer 51

All-Star Hua-Jun Li - MSFT

http://forums.asp.net/t/1488928.aspx

Based on my experience,your server code has something wrong, please change it.

Firstly, you should add the following code at the begining of  Page_Load event.

Response.Clear();

Secondly,you can't put 'Response.End();' into try catch block, it will cause the problem you mentioned.

You can remove it and use it directly.

Response.End(), aborts the current thread. if you call inside a try block,you will catch the thread abort. if you use a try block, you'll need to catch the abort and rethrow it.

Another way you can use 'ApplicationInstance.CompleteRequest' method instead of 'Response.End();'.

Please check the following link:

http://forums.asp.net/t/984756.aspx

http://bytes.com/topic/asp-net/answers/769508-error-response-end-unable-evaluate-expression

http://geekswithblogs.net/vadivelkumar/archive/2006/02/25/70703.aspx

 

---

xavier luz

Answer 52

Wes,

Thanks!!

I was facing same problem,  now it works fine.

Thanks.

 

---

"Knowledge Shared Is Knowledge Gained"

Answer 53

hi please remove Response.End(); from your code it will work

Answer 54

I found the same problem while I was using a Thread to get web response in my application. After removing the try-catch block the error exception was gone but didn't find why the thread work imperfectly like abruptly kicking out the incomplete thread.

Still can't understand or resolve the problem. 

---

Prithwi Raj Biswas

Answer 55

I resolved it by removing ajax function in aspx file.
try
        {
      Reponse.clear();
       ...... //code to export excel file.
            Response.End();
        }
        catch(Exception e1)
        {
            throw e1;

        }
I am using above code and got the same error, and I resolve the problem using below methods:
1, remove try catch code, 
2.remove Ajax code in aspx file, 

work well.

Answer 56

This work with above solution

Thanks

 

Answer 57

Hi Friend,

         Your code

Response.ContentType = "application/octet-stream" was saved much more time.

 

Thank you so much

 

Regards,

Karthick Raj

Answer 58

For example, If you are using Response.Redirect("test.aspx") use Response.Redirect("test.aspx",false). This will solve the problem.

For further detail...

http://support.microsoft.com/kb/312629/EN-US/

Answer 59

It worked for me... Looking for solving d issue since last 2-3 days. but could not get success.

Thanks