Reconnect to a disconnected Excel COM Interop instance - c#

I have a 3rd party app that is exporting data to Excel using the Excel COM Interop. There is a bug in their program causing it to fail before it makes the Excel instance visible. However from where the exception is happening, according to the displayed stack trace, the information I need has already been written out to the Excel Worksheet.
Is there any way to use the Microsoft.Office.Interop.Excel namespace to connect to a existing excel instance instead of it generating it's own? Or is there any other way I could make that orphaned Excel instance visible so I can save what it completed?
As a note, the EXCEL.exe is still visible in task manager after the program closes so the instance is still live and running after the app has disconnected.
More Details: What the program is doing is exporting a report from it's own (proprietary) database, however for some reason some record in the database became malformed and causes a Integer Overflow error to occur while the report is generating. Looking at the stack trace it appears this integer overflow is happing while it is generating the summery at the end of the report.
For my uses I do not need the summary just the line items from the report, so I hoped to see what work it had done so far but the EXCEL.exe instance it was communicating with is not visible.
If I run the report for a different date range the report generates fine, it is just something about one record on one day that causes this specific set of inputs that causes it to fail.
The support contract with the provider of the app as expired and management is not interested in renewing it as we are in the process of switching to a new vendor (that is why the report is being generated, to be used as the data-source for the data conversion). So I have been tasked with "fixing it" so the data can be moved over.
Final Update: The reason I asked the question was solved. I was able to go through each record via the program itself and I found the record that had one of it's fields set to 16274176.00 (normal values are in the 100's (and don't ask me why what appears to be a float causes a Integer Overflow error)), once I changed that to 0.00 the report printed fine. However I still would like to know if there is a answer to my original question as I think it would be a useful tool in my toolbox.

In regards to your original question, I think it actually might be a possible duplicate of what have been asked here: Get instance of Excel application with C# by Handle
A couple of the answers given points to this blog post: Launching Office Apps Programmatically which gives you a palette of options of how to connect to an already running Office application from managed code.
The blog post as well as the answers given also contains sample code to illustrate how this can be done.

Related

Printer spooler api number of copies

I really could use some help, this is a question that alot of people are asking on the internet. I have different setups, tried different ways of testing, it's very frustrating.
First setup:
local printers
local running code
print from pdf or notepad: SUCCES (number of copies are 2)
print from word: FAILED (numberof copies is 1)
Second setup:
local printers that are shared
local running code
print from other computer to shared printers
number of copies isalways 1
Sowhat is everyone missing? What happens that some fields are missing while the printer still should know what to print? What does word that also happen when you print from another computer? Can someone tell me why somethings in windows are so terrible? Everythingshould pass the spooler, sowhy isthedata wrong?
Kinds regards!
A printer prints sheets and pages, so copies is converted to pages at some stage.
The notification data you get depends on both the application that is printing and the system and driver components handling the spooling and rendering. In my experience the data cannot be relied on, and the best data is obtained by parsing the spool file. This may or may not contain the number of copies.
Word has had the "copies problem" for a long time. There was a patch to supposedly fix this, but another opinion is that it's because it uses an unusual way of printing. I'll quote some of the link contents here:
With the infamous Word Copy Count bug… the dmCopies filed is 1 in the
SHD. The correct value is found in the DEVMODE record in the SPL file
(if it's an EMF spool).
The only other way i found was to monitor the PrintedPages field of
the JOB_INFO_2 structure, when the job has been sent to the printer,
and see if it is a multiple of TotalPages.
[...]
What happens is not a Word bug, but a Windows bug. Word calls startDoc
always with copies set to 1. After that calls DocumentProperties and
makes the change in dmCopies and calls ResetDC to make the update. It
is a strange way of printing but not wrong. The problem is that the
shd file and printer_info is not updated with this information, just
keeps the Devmode info set on the StartDoc call.
But the call to the ResetDC generating a new DevMode is kept on the
SPL file. You can get that info too if you hook DocumentProperties
API calls.
Thank you for the answer. Is there a way of catching the document properties when they change?
The JOB_INFO_2 structure does have the same total_pages as pages_printed. So that is not a solution.
The SPL File does contain the QTY for the printer i tested on which is correct. BUT we tested on a lot of printers and we see the QTY is not Always set. So not a 100% solution. But already a good fallback.
So if i can catch the document properties without calling the SPL file that would be wonderful because i guess that's where everything is correct. Isn't it?

Unexpected behavior when refreshing internal data connections in Excel

I have faced a big and inconvenient problem with Excel spreadsheets that have internal data connections (queries that selects ranges of the own workbook) in them.
I wiil start by showing the problem e exposing how to reproduce it.
Problem: if I have some internal connetion and another instance (pay attention, instance, not other workbook) was already open, when refreshing that connection, the same workbook (which have the internal connection) is instantly opened in readonly mode in another window...
Why this occurs? The problem is that I'm developing a .NET automation application for Excel and this behavior breaks some process flow (because the readonly file stays open and sometimes it causes a non refresh in the original workbook)
To solve this problem I began to use the same instance if it is already open, but this is not the best solution because I need to handle the concurrency when running several VBA macros in the same instance via .NET Interop.
Here a workbook for those who wish to test this issue that I presented (just change the string connection inserting the new file path in your computer):
Excel File for Test
I recorded a video to show you the issue with more details and how to reproduce it. Please, take a look:
Video
I hope someone knows how to solve this problem because I've been searching for this several days...
Thanks
Obs.: The Office version is 2013

C# Word automation makes Windows Explorer crash

I have written a C# program which import a product list from a .xlsx file and let the user create an order based on that product list.
When the user is finished, the program builds one or more system specifications based on the order.These specifications is written to a .docx file. I have Office 2007 installed on the computer and are using the Microsoft.Office.Interop.Excel and the Microsoft.Office.Interop.Word namespaces.
The problem:
After I have runned the program, Windows Explorer crashes very often and has to restart. This happens when navigating in folders or when right- clicking on folders etc.
This also happens after the program have been closed and the only solution to make it stop is to restart the computer. It seems like it only happens when I have created the output files (.docx). If i start the program and use it like I normally do, but without creating the word files, the problem don't seem to occur.
After the program have created the output files, Word gets "Visible" to the user for manual editing. The user closes the word application when finished editing the documents.
What can make the Windows Explorer crash when running word automation?
I really need help on this one. Any suggestions are welcome.
After execution, do you have ghost excel.exe and word.exe processes remaining?
These ghost are likely to make the system unstable.
You're likely not releasing properly the COM objects you instantiated via automation.
Use Marshal.ReleaseComObject(yourobj); on each and every COM objects you instantiate. It's a real pain, I know.
Note: be sure that you don't instantiate COM objects without knowing it:
mySheet = myExcelObject.workbooks[0].Sheet[0] won't just instantiate a sheet object, but also a workbook object.
Rule of thumb: never ever use a secondary property on a COM object ( foo.bar.baz ) and release everything.
Final note: don't use office automation at all on the server, it's bad, per Microsoft own words, there are fully managed libraries for that.

Better option for hosting MS Office documents in custom app?

I am currently hosting an IE Browser control in a .NET (2.0) Form and using it to load Office files such as Excel and Word thusly:
_ieCtrl.Navigate("C:\\test.xls", False);
The hosting and loading works well except whenever I navigate to a file I am presented with a dialog that asks whether I want to save or open the file. (This is standard IE file-download behavior.) I always want to open it of course and I do not want the dialog to show.
Another issue is that when I close the window that hosts the IE control and the Office doc the document does not close and remains open on disk. This means that subsequent attempts to open the same file via my app or the native office app will fail because of the sharing violation.
Is there a programmatic way of avoiding this dialog and cleaning up resources afterward? I am asking for a programmatic answer because web research has only yielded solutions that entail modifying OS-level settings.
Bounty NOTE:
I am open to any solution to this issue that will allow me to:
Host an Excel spreadsheet inside my application
Work rather transparently (avoid usability issues like the one described above)
Avoid having to make any OS-specific changes that may affect other applications (especially icluding IE)
Is zero additional cost (no licensed 3rd party libs please) Code Project and other open source resources are OK
Not mess around with the DSO Framer ActiveX control, unless a stable version is developed/discovered
Is your intention for the user to be able to work with the Excel file in an Excel-ish way (i.e. columns, rows, formulas, etc.), possibly saving it back? If this is the case, I can't see how you can solve this problem well without relying on COM Interop with the Excel object model or by integrating third-party libraries to work with the Excel sheet. I know you said no paid solutions, but there are some feature-rich 3rd-party controls out there just for working with Excel files within applications.
I noticed in your comment to SLaks that the final product is a "dashboard of sorts". If your intention is to design a a custom dashboard application, have you considered parsing the Excel file(s) to extract the data and then presenting it in a logical manner within your application. This removes the need to directly display and work with the Excel file while still allowing you to work with the data inside that file. If you are trying to get the data outside of the file, here are two approaches among many:
You might consider using the Excel object model and COM interop to read the data from the Excel file into your application. Granted, this includes a dependency on Excel being installed, but it is a possibility. This article has some great code for getting started with reading Excel files in this way.
A better way might be to use a library that doesn't have a dependency on Excel being installed on the local system. This answer suggests using the Excel Data Reader library, available on CodePlex.
I know this answer side-steps your original answer of "hosting MS Office documents in [a] custom app," but in case what you're really interested in is the data inside those Excel files, hopefully this answer will prove helpful.
This is a horrible hack and should only be considered as a last resort: SendKeys.Send("{O}");
http://msdn.microsoft.com/en-us/library/system.windows.forms.sendkeys%28VS.71%29.aspx
Something similar to
_ieCtrl.Navigate("C:\\test.xls", False);
(code to sleep or wait may be needed here)
SendKeys.Send("{O}");
Basically, you send the "o" key to the dialog so it presses the "open" option. You are simulating a keyboard presses to click the "open" button. It is hackey because
1) you may need to wait in between
calls. If you send the o key before
the dialog is up it will be missed.
Hopefully the navigate call is finished when the dialog pops (dont know behavior of control in c#). You may need to experiment with the time since different computers will open faster\slower
2) If the dialog is not shown on a
computer, you will be inserting "o"s
into it. This may cause problems when
exiting because it may popup another dialog to try and save
the changes. May be able to prevent this by opening it in read-only mode
3) Different versions or windows may need different sendkeys commands. For example, you may need to send "o" and them the "{enter}" key
4) Probably more :)
If you want to open the file in a separate Excel instance (not embedded in the WebBrowser control), you can simply call
Process.Start(#"C:\Test.xls");
Office was never meant to run in embedded mode, not in a web page or in an ActiveX Document host. Microsoft had time and time again given us the warning. From pulling dsoframer from the knowledge base to skipping the BrowserFlags registry key in Office 2007.
Move to Office add-ins, Excel Web Access or Office Web Apps as quickly as you can.

App hosting Report Viewer crashes on exit after export

We have a .NET Winforms application that hosts the Crystal Reports Viewer control (Version XI). It works well for the most part but when an export of data from the viewer is performed the application will crash on exit and in unmanaged code. The error message is not very useful and just says that an incorrect memory location was accessed. No other info such a specific DLL etc. is provided.
This only happens after the viewer is used to export a report to CSV, XML etc. My guess is that at some point in the export process Crystal creates a resource that attempts an action on shut down to a parent window (perhaps) that no longer exists.
I've seen a number of memory leak and shut down issues with Crystal but this one's new. Has anyone seen it and come up with a workaround or has ideas for workarounds?
So far we've tried explicitly disposing of all crystal-related objects, setting to null and even setting a Thread.Sleep cycle on shut down to "give Crystal time to clean up."
Update:
The crash happens only on shut down (so not immediate)
All export formats work
All export files are created properly
CR is installed on the same machine as the hosting .NET app
not sure about exporting from the IDE... is that even possible?
Check your code to ensure that you only open the Crystal Application object once during the lifecycle of your application. This will prevent excessive memory usage, usage that may be causing your crashes. Obviously, you can open and close reports at will.

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