I am trying to debug some code in my ASP.NET web app.
I set a breakpoint in one of the page events of the page's codebehind, and this once came up with a special icon in place of the red breakpoint saying symbols have not been loaded and the breakpoint will not be hit.
This error has not repeated itself but why can't I hit the breakpoint?
Also, when I press stop, I get a popup in VS stating:
Stop Debugging In Progres...
Debugging is being stopped but is not yet complete. You can force debugging to stop completely, but any processes attached may terminate.
This window will automatically close when debugging has completely stopped.
Completely stop
I also don't get the website appear in my browser either when starting to debug. :(
To make things worse, I have a line of code like this in my page's codebehind:
RssFeedSites = opml.Parse(filestream);
I am putting the problematic breakpoint on this line. But I have a programatic breakpoint in the Parse() method of opml, but this does not get hit, either.
Thanks
Could you check if the dll is perhaps in the GAC? If it is it is probably an older version and the GAC has priority over local dll's. So if the dll is in the GAC visual studio is using that (older) version instead of the newly built one.
the debugging host could not find the correct pdb's to match your executable or the debugging host is failing.
Check your build, are your PDB's all up to date and in the correct directory to be found ?
Check the debugging host process if its having problem. If your using visual studio hosting process, then has the vshost.exe process somehow terminated prematurely ? If your remote debugging, check the remote debugger. Check your web server as well. If the debugging host process fails to respond, visual studio will be stuck when trying to debug.
I don't recall the specific reason for the message when I have seen it, but I always ignore it, because the symbols get loaded when the page is executed and it always hits the breakpoint assuming it's in the process flow of the page.
If you can't hit ANY debug points and you are running from local IIS, you will need to attach to the working process(w3wp.exe). Tools->Attach to Process.
Related
We are developing an (internal) web service based on asp.net 4.8, with a fairly extensive REACT SPA front end.
For debugging purposes during development, we run an IIS server on the local (development) machine, and we do something separate to run a proxy web server for debugging the .js front end SPA (not relevant to the question at hand).
When we start up a Debug session in Visual Studio (2019), VS starts with "Contacting web server to start debugging" and then locks for a time. It clearly does something to start the web server (w3wp.exe), and waits for some reply, before doing what it is told to do in the "Start Action" section of the Web tab on the project properties page.
This is problematic behaviour because it does not attach to w3wp.exe until after it finishes it's "contacting web server to start debugging" operation. This is a huge problem, as our w3wp.exe starts doing all kinds of things that we have no visibility into.
So, can anyone explain to me:
What does VS actually do to "contact the web server"?
Can this be controlled? If so, how?
Can I get the debugger to attach to w3wp.exe right away?
Why does w3wp.exe start up and load its collection of binaries, only unload them and reload them, sometime multiple times?
In short, what the actual heck is going on under the covers at startup?
This (Identity Server 3 Contacting the web server hangs when launching debug mode) question and answer seem irrelevant to my situation
I note the field Override application root URL in the Servers section of the Web tab of the project properties and had hoped this might have something to do with it, but I cannot see any relation.
Partial answers that I will either edit as I find more info, or modify if others correct me, or delete if someone answers completely. The answers to (1) and (2) above are this:
VS obtains the URL of the target web site (I will call this targetServer) from the Project URL entry in the Servers section, Web tab, of the Properties page for the web project. This actually comes from the <webProjectName>.csproj.user file in the project directory. Depending on the selection of the drop down specifying the server type to use, it comes from:
IIS server (<UseIIS>true): the <IISUrl> element
External Host (<UseCustomServer>true): the <CustomServerUrl>
IIS Express: unknown
WARNING: When opening a project with <UseIIS>true, Visual Studio has the very nasty habit of interfering in the setup of your IIS server: it insists on changing the "Physical Location" attribute of the IIS server (that is, the server or virtual app, however you have it set up) to point to the project directory of the web project. Using the "External Host" option avoids this - see https://stackoverflow.com/a/48753054/1082063. (All other discussions of this issue that I have seen incorrectly say this cannot be controlled.)
VS then issues a request to the url <targetServer>/debugAttach.aspx, and the request shows as neither a "GET" nor a "POST", but a "DEBUG", whatever that is. Not sure what VS expects back from this before doing the specified Start Action
Presumably after VS gets some reply from its DEBUG request, it will attach to the process that resulted from this request. Not sure how it knows which process to attach to - perhaps the debugAttach.aspx returns process information?
VS finally executes whatever Start Action is specified in the section of that name on the Web tab of the project Properties.
I strongly suspect that the answer to (3) above is that one cannot get VisualStudio to attach any earlier than it does because it must use the information returned from the debugAttach.aspx request to know which process to attach to. However, putting the line System.Diagnostics.Debugger.Launch(); at the start of Application_Start will allow you to attach the debugger earlier when necessary. (In practice, once you get Application_Start correct, you seldom need to debug it.) See this: https://weblog.west-wind.com/posts/2011/Dec/15/Debugging-ApplicationStart-and-Module-Initialization-with-IIS-and-Visual-Studio for a very good article on the subject.
(4) was a result of quirks in our Visual Studio setup. The initial "hack" used to get around the WARNING in answer (2) just above, was to have a web site with a dummy "virtual path" and have the IISUrl element in Visual Studio point to this virtual path. Then VS could change the Physical path of this virtual path, and we didn't really care, because our Start Action was to start a proxy server for debugging .js in any case. The issue was that this resulted in two calls to Application_start, running on two separate threads: one for the main server and one for the virtual server. Because one of these was happening before the attach happened, we never knew it was happening and it was never caught in a break point. When our application_start became long (timewise - this is not a web server for public consumption...), the two executions of application_start became a nightmare.
The issue you're seeing in IIS is that VS is not launching w3wp.exe, but rather Attaching to Process. In order for VS to attach though the EXE has to be running first, and the time between starting up and attaching (if not already running) ends up being too late to catch the ASP.NET app initialization logic in Application_Start and Module initialization.
As mentioned in my old post there are several ways you can get this to work:
Restarting the application when the debugger is already attached
(by making a change in web.config to trigger an AppDomain reload)
Adding an explicit Debugger.Break() call in Application_Start
Use IIS Express to debug startup code
I have a project that has, amongst other things, one web application (mvc) and one WPF application. For the part that matters, the WPF app connect to a WCF service hosted on the website.
What I want to achieve is that when I press Ctrl+F5 (start WITHOUT debugging), the build process kicks in (if needed, in other words, the default VS behavior), the WPF app launched, and if the webdev server is not launched, that it get launched too, but without opening any page on my browser (I'll manage that myself).
I managed to get that working as I want (configuration below), but every time I do a Ctrl+F5, I get a popup from VS that says
Choosing to wait for a request from another process without enabling
ASP.NET debugging results in nothing to debug.
I value the information, and that seems to match pretty much what I'm trying to accomplish anyway, but now, instead of having to close a useless tab in my browser, I have to close a modal dialog. Not a big improvement from my point of view.
So, how do I prevent this popup to show up ?
Additional information:
I don't want to start in debug mode (F5). If I need debug for the website, I'll do my usual (attaching to the webdev server).
I want the webdev server to be running all the time from the first CTRL+F5.
I don't want to publish it on IIS (even the express version)
The solution startup option is set on "Multi startup project" with the WPF app on "Start" and the website on "Start without debugging" (setting it on Start doesn't change anything, except that I also get the popup when debugging with F5 directly).
The website has its start action configured on "Don't open a page. Wait for a request from an external application". The ASP.NET checkbox in the Debuggers is checked.
Internet had not been a big help so far, so all my hopes lies on you SOers !
Edit
It seems that it was flagged as a bug, but I don't see any reference in what version it's supposed to be fixed...
Also, I discovered my question is a duplicate of this one.
I actually found another way : in the start actions, you can set it to "start external program" and reference a self quitting program. I used "C:\Windows\System32\PING.EXE". Not perfect, but also less annoying than the previous solutions.
I am running/debugging an asp.net mvc3 application from within Visual Studio 2010.
Anything static in nature is not called when I re-run the app from within Visual Studio.
(or even something simple like Application_Start())
Each time I want to run the webapp 'properly' I need to kill WebDev.WebServer40.EXE in the task manager before anything static is called again.
q1) Is this normal, and if Yes, why?
q2) If no, then I would expect the ASP.NET Development Server to be restarted each time I restart a debugging session. How can I turn this on?
UPDATE:
Recompiling sometimes causes Application_Start to be called, not always.
I've resorted to calling a batch file in the prebuild, eg
kill_WebServer40.bat
which contains
taskkill /F /IM WebDev.WebServer40.EXE
exit 0
If you embed those two commands directly into the pre-build textarea your compilation will fail if the WebServer isnt running already. This linked helped fix that.
Surprised this wasn't discussed more/previously - when developing an app, as if you have any static data/caches and you want to run the application 'clean' you would run into this issue.
Yes it's normal. It will restart if you touch the web.config or recompile. The development server continues to run the application in the background after you stop debugging.
You can stop the development server in the task tray by right clicking on the icon and choosing stop.
There isn't a way to force a application restart every time you hit debug. This would only be needed for the edge case where you are debugging application start up. Just hit rebuild before debugging and it will have the desired affect.
Alright, I've been searching forever and can't find the answer to this.
So on my work computer I run Windows 7 and Visual Studio 2005. I have a ASP.NET project (2.0) and let's say I hit F5 and start debugging. Now, once a page is done rendering I can edit the content or the codebehind code of the page without it throwing any error messages (just like if the project was stopped). Then if I save the file and hit refresh on the current debugging browser, it'll take a minute to recompile the project automatically and then refresh with the recompiled code. I can ONLY change the code in the ASP.NET project, not any class libraries that the ASP.NET project is dependent upon. I can also set breakpoints and it'll hit them (so it's not like the debugger is not attached or something).
Now on my home computer, I run Windows 7 and Visual Studio 2010. I have an ASP.NET project (4.0) and let's say I hit F5 and start debugging. Now, it doesn't matter if the page it done rendering or not - I cannot change ANY of the code behind, although I can change the content. If I attempt to I get a message saying
"Changes are not allowed while code is running or if the option 'Break all processes when one process breaks' is disabled. The options can be enabled in Tools, Options, Debugging."
That being said, if I put a break point, refresh the page and hit the breakpoint THEN I can change the code and then hit F5 to continue.
So my question is - what EXACTLY do I need to do to get it to work like my work computer? It's REALLY annoying to have to stop the project or be clicking breakpoints all over to edit one little piece of code (especially when I'm so used to not having to do that at work). Is this some change in Visual Studio 2010 or something? From what I've read, how it's working at home is the real "Edit and Continue", but I can't figure out what to call it on how it works with my work pc.
Another difference (might be of help):
I set it up so that my IIS goes to the project folder, and then run the project outside of the debugger on both my work and home machines.
Now on my work machine I can make a change to the code and when I hit refresh on the non-debugged browser it'll do the same pause for recompile and then refresh the screen.
On my home machine if I make a change to the code and save it and then refresh the non-debugged browser it will not recompile the code.
So this makes me think it's some IIS setting in the end to make it auto-recompile? It clearly doesn't seem to have anything to do with VS since I'm not even going through the VS debugger to access to code at that point.
Just my thoughts: maybe you use on the work WebSite project, but at home WebApplication. In case of application all code will be compiled in the single DLL and changes should be recompiled first. In case of WebSite - each page compiles in different DLL and you can chage any of the page and it will recompile it.
My company gave me a web application project and I went to debug it and set some breakpoints and they dont fire. I am using Response.Write all over the place to debug. Anyone know what maybe going on?
I am running the application off my localhost I was pushing F5, but since the breakpoints dont hit by making changes and adding Response.Write statements and clicking save then refreshing my browser I get the changes for whatever reason.
Hovering over the breakpoint it says "The breakpoint will not currently be hit the source code differs from the original version"
Another tidbit is I created a new web application project and created a breakpoint and it works, its only specific to this application it seems like, but dont know what it could be?
Hovering over the breakpoint it says "The breakpoint will not currently be hit the source code differs from the original version"
Try this:
Close Visual Studio and make sure any instances of ASP.NET development server are closed as well
Delete everything from "C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files" (where v4.0.30319 is the version of your .NET Framework)
Definitely need more info, but I would check that your are building with debugging symbols to cover the dumb stuff.
Okay, after reading the comments posted on your question I was making the following assumptions.
You are running using the built in VS development server
You are compiling in debug mode
You've set debugging true in your web.config
I've seen this problem before and for me it's been resolved by restarting Visual Studio.
Assuming that you are running on IIS on the same machine that you have visual studio installed:
Have you attached to the application pool process
Is you code the same as what is deploy? (Is the latest version deployed)
Are you logged in as administrator?
Are you running visual studio as administrator?
Just to make sure, you are running in debug mode?
I ran into this problem a while ago as well, instead of using response.write, you could try outputting the data to a label control's text value instead to see the values of your code.
It's a bit of a sloppy work around, but I couldn't figure out why that one particular project I was working on didn't let me debug it.
This problem is, for me, mostly caused by a mismatch of the loaded dll files (symbols) by webserver, and those that the project are pointing to when you try to breakpoint. It's different files. I have located different causes. One could be a simple hang-up by webdev instans (force shutdown. But also that there occur some kind of mismatch if you got different compilation methods between project within same solution as the web project.
This desc may not be your exact problem, but perhaps it will lead you into right direction. I find this often being a dirty unlogic error that just are irritating (but also completely fixable without data loss or reconfiguring, when u understand the trick).
I had the same problem, and it turned out only Internet Explorer works with debugging and breakpoints. To avoid having IE as my default browser, I changed the launch settings in the .Web project to run IE with the path as command line parameters.