Excel hangs when printing the first time from ASP.NET webservice - web-services

We are using Excel to convert SpreatSheetML to XLS in an ASP.NET webservice. Moreover, if the user checks the right checkboxes, we spawn a thread that uses Excel to print the spreadsheet.
Recently, we have deployed the app in a new environment, and then we started having problems: the first time someone tries to print, Excel seems to hang on the server - i.e. the call to the PrintOut method on the workbook never returns.
But if we log in to the server as the application pool identity and open Excel, send something to the printer, and close it again, printing will work from then on!
I suspect that Excel is showing an invisible dialog - the symptoms are the same as we had earlier, a time when Excel seemed to stall on a "cannot use object linking and embedding"-dialog that appeared when Excel opened.
I know that using server-side Office automation is bad, but this is a legacy app that is very hard to change, so please don't just advise me to re-design our solution.
Has anyone had any experiences with this kind of behavior?

Well, noone seems to have had this problem.
The really weird thing is that my night jobs (ordinary .NET .exe) are perfectly capable of printing - it's only my web services that have this problem.
So I solved the problem by doing what I should have done long ago: I made a simple Windows service with Topshelf, that responds to some MSMQ messages and does the printing, and then my web services can order print-outs via a message queue.
Much nicer in every way!

I've had no end of problems (poor performance, hanging processes, crashing processes etc) using Microsoft Excel, Word and PowerPoint through interop in a web service to print Office documents to PDF format. I too have faced problems that I suspect are because of invisible dialog boxes (maybe a file is corrupt, read-only recommended has been set, file is password protected, or whatever).
I know there are tools available that don't use Office, but they are very expensive. My solution was to switch to automating OpenOffice. OpenOffice seems to be much more stable, and I've left hanging processes and the like behind.
So, while I suppose I am saying "don't automate Microsoft Office", I'm not suggesting that you abandon automation altogether; just that I've had much more success automating OpenOffice than Microsoft Office.

SpreadsheetGear for .NET can read xls or xlsx workbooks and can print to the default printer without displaying any dialog boxes (see the WorkbookView.Print() method).
You can download an evaluation here.
Disclaimer: I own SpreadsheetGear LLC

Like many people, I have seen this sort of behavior. It is caused by using the Office APIs in a server, especially a multithreaded ASP.NET application.
However, you've said you don't want to know about not shooting yourself in the foot, so there's little more to say. You seem to be trapped by the consequences of earlier foolishness.
OK, stop me if you've heard this one:
A man asks a question on StackOverflow. He says, "SO, bad stuff happens when I automate an Office application from inside a service". So, John Saunders says, "So, don't automate the Office application from inside a service. Automate it from inside a desktop application, as Microsoft intended to be done."
When a request comes in for something that requires Excel, you should create a process running a Windows Forms application. The application may have to start with no window, or you may need to start it in the context of a Remote Desktop connection. In any case, the task to be performed may be passed as a command line parameter, or the program can host a WCF service to have commands sent to it.
This program can call Excel just like Excel expects to be called. It can probably even handle more than one command to Excel (one at a time). However, if it hangs, the process can be killed and another one started.
I've never tried this, but it sounds like it would work better than trying to get Office Automation to do something it was not designed to do.

Related

BIRT integration in exsiting C++ application

I hope you are doing good and i really appreciate your help here for my query.
We have our system T3000 written in C++ (http://www.temcocontrols.com/ftp/software/9TstatSoftware.zip and codes are available here https://github.com/temcocontrols/T3000_Building_Automation_System).
I am trying to integrate 'BIRT reporting tool' in my C++ application. I want to create report based on the data available in our T3000 system. I think BIRT is embeddable (??). We don't need to compile and change the project, just need to be able to call it from T3000.exe mainly.
My thinking is we may put one menu label in existing T3000 and try to display report in user single click.
Can you please help me to solve my issue with 'BIRT' ? I really appreciate your answer.
Regards
Raju
Well, the answer depends on what your definition of "embeddable" is.
BIRT is written in pure Java.
I could think of 3 different ways:
Of course it is possible to integrate Java code into an existing C/C++ program (see Embed Java into a C++ application?).
You could just use the BIRT runtime engine and generate the report as PDF or HTML from the command line (that means, basically you call the java executable from your program with several arguments). See Birt - How to run report engine on the console? and http://eclipser-blog.blogspot.de/2008/02/automatic-generation-of-birt-reports.html for more information.
You could run a Java web server like Tomcat in a second process and then start your report by calling a http URL (e.g. you could use the included Servlet example). See http://www.eclipse.org/birt/documentation/integrating/viewer-usage.php
Similar to 3. (see below)
Some notes:
The second option is slow, due to the Java and BIRT engine startup overhead (this may take several seconds). With the first and third option, the startup overhead is or can be minimized to only once (and for each report).
For the second and third option it may be necessary to modify the existing code of the example programs to suit your needs.
The first option is probably the best for an industry-quality solution, but it is also the most difficult to develop.
Anyway, Java skills are necessary IMHO.
If you plan to run this on a SOC instead of a PC, take performance into account.
Is a Java-based solution well-suited for this kind of hardware? BIRT needs quite a lot of RAM and CPU (for a SOC). Hardware like the Raspi 3 should handle this quite easily, I reckon.
I integrated the BIRT runtime into an existing Python application (all this running on an application server) in a fourth way: I wrote a listener program that listens on a TCP socket for BIRT tasks. It uses a pool of worker processes (written in Java) which in turn use the BIRT report engine to generate the output. The client program (here: written in Python) opens a TCP connection to the listener and uses this socket to tell it which report to generate (including report parameters and destination file name). The listener program then in turn chooses a worker process for the task and gives the task to the worker process.
So, basically, this fourth option is similar to the third one, with two differences:
The communication is socket-based (instead of http), allowing bi-di communication.
The architecture is multi-processes instead of multi-threading. We choose this because very large reports could cause out-of-memory errors for otherwise unrelated reports that just happen to run at the same time. It's the same basic architecture Oracle chose for their reports server.
However, developing the programs took months.
HVB: I have to give you more than a simple thanks for the explanation above, this info will save us time I am sure. Raju will be sharing our experience after we get into the project a little deeper so others can benefit.

How to create a login application with Visual Basic (using WebHttpRequest)

Hei there, I'm not experienced at all in C++ as I need to start learning year the next year at my university, though, I've been creating a browser based game and I'm looking for someone to transform it into pc app.
Though, I'm wondering how to make that application send a http request via POST to a file on my webserver with the username / pw.
After all the tutotials I've been reading, I concluded that none worth spending my time with, because they all based on own database, and I'm looking for one that connects to a maestro server and requests the data from there.
This may not be the answer you are looking for, but you may consider two alternatives to a more pure C++ application.
If you already have a working browser game, try to take that same code and put the html/javascript/whatever in a file and give the file a ".hta" extention. It basically opens inside a browser to run your files, but it acts more like an application from the user's viewpoint. (And, as much as I hate Windows, they're pretty fun to create if I may say so). However, your source code with this option is easily read because it can be renamed to a text file (or html file).
You could use Visual C++ (or VB.net, which you have tagged to the question, as well as "Visual" C#) to create an application which mostly consists of a browser view. It could be a "standalone" application (however would rely completely on the .Net framework - may or may not be what you want) that basically accomplishes the same as the option above, but adds that you can "hide" your files inside your application.
Using the two above alternatives, you could make an application relatively quickly that would load your files, which I assume you have already created. Note that neither of the above alternatives will work on anything other than Windows OS's.
If the two above alternatives are not what you want, or if you have questions about either one, I'd be glad to attempt to help.
I've been able to find a friend that would do it in Delphi because I wouldn't want users to download net framework just for this ap.
So the program that would fit most for any apps is Delphi Prism XE (even if it's an addon of Visual Studio)

Upgrade Path For Legacy Reporting ("Embedded" Access 2003)?

Update: Albert D. Kallal has kindly started the discussion off, and to get some more opinions I'm adding a bounty.
This is a nontrivial question about maintenance of a legacy application myself and two other developers support. We are not the original developers, and the code base is 300,000 lines of MFC and business logic tightly coupled together. We don't know every single line of code 100%.
We do know the code behind the major components, and we know that it's poorly written. Our objective is to refactor the application out of 1995 and into 2010. Between the three of us there is (in aggregate) enough experience in software architecture and database design for us to fix the components that are poorly architected in code or incorrectly modelled in the database, but we don't have a lot of experience with modern reporting systems. Thus my question (once you get to the end of it...) is about reporting systems.
For anybody who reads this entire post, I am appreciative of your time. For anybody who reads this post and replies with solutions, experience (or sympathy!), I am both appreciative and thankful.
At work I have inherited the maintenance of an Access 2003 database that contains approximately 250 reports (and thousands of supporting queries) that acts as a reporting engine for our application.
The reports all have swathes of VBA in them for particular formatting or pulling extra information into the report. For this reason we are entirely locked into the Access platform, we can't use tools like BIDS to import the Access report objects without messing around to make the report display the same without VBA.
So to get ourselves out of this Access solution we need to put some time in going over every single report. Which means we're looking to pick the best longterm solution, since we're going to have to redevelop every report regardless of the platform we choose.
Furthermore our customers have a choice of Microsoft Access or SQL Server as their database. This means that all our SQL has to be written with the lowest common denominator in mind - JET SQL. We've got some wiggle room to drop support for Microsoft Access, but we'd need to build a case for it. If the best reporting system we can identify has strong support for SQL Server but little or no support for Microsoft Access this will accelerate us dropping support for Microsoft Access as a database.
The overall implementation of the report system is quite mediocre, when we want to display reports in our application we start a Microsoft Access process, find its window and reparent it to our application, strip off its window styles and then use the Access.Application COM interface to invoke some VBA that creates linked tables to the database (either a Microsoft Access MDB or a SQL Server database) and then opens up the report we want. Probably the only supported part of the process is using the public COM interfaces, the rest is an ugly hack. The other components in the application are equally underwhelming.
To "fix" our application we've got a new development plan, with development of our application split into (approximately) three parts every year.
4 months upgrading our application to support the latest government legislation in our industry
4 months delivering a new major feature
4 months "consolidation" (fixing what is broken)
We're currently at #3 now (for this year), and we really want to take advantage of the downtime to fix up the application, refactoring the major components. We have three developers, and want AppName v5.0 out at the end of 2012 (it's currently AppName v4.12). This gives us 36 months of development effort to approportion between several components (user interface, underlying database structure, reporting, etc) over the three consolidation periods we will have before then. The sum of the components that we fix will give us v5.0.
We've scoped out what we'd like to do with most of the components except for our reporting engine, and I'm posting on SO in the hope of getting some good ideas, or at least a feel for the work that's required.
I have two ideas for improving our reporting system. Both of them involve a moderate amount of work, and there is one consideration that neither solution addresses completely: in addition to the reports that we develop, our customers also have the opportunity to request bespoke development of reports. They're customer-specific, we take their Access database, augment it with their report and give it back to the customer. There's hundreds of unique reports out there - unusable if we turned the old system off. (And we have to turn the old system off eventually - we don't know how much longer we're going to be able to mess around with the Microsoft Access window to make it look like an embedded report. We already have two distinct code paths for Access 2003 and 2007. What if we can't hack up a code path for Access 2010 and all our customers have to use Access 2007?)
For both ideas, the intention is to stop supporting our current reporting system and let it run for as long as it will without maintenance. Maybe we can hack in Access 2010 and Access 2014 support, and the customer reports that were developed keep putting along for 5 more years. Over time, we'd migrate the most commonly used reports from the old Access database into their new format.
Idea 1: Microsoft.Reporting.WinForms.ReportViewer
The first idea is to write a wrapper around the ReportViewer control as a replacement reporting engine.
We'd need to move the project to C++/CLI (already on the cards), and instead of having to launch an entire process each time we needed to view a report we could simply instantiate this control. A bonus of this that the RDLC files that contain the reports are much easier to version control in Subversion than the Access 2003 database we currently have (we use Visual SourceSafe because the tools to integrate SVN with Access don't work well with the size of our Access database). The visual designer for RDLC files is also nicely integrated into Visual Studio.
This is more of an evolutionary rather than revolutionary change to the way we do reports, the ReportViewer control will take an RDLC file that has the report layout, and our application will take care of querying the data. Because our database might be SQL Server or Microsoft Access, we still have to write simple JET SQL. We're gaining better reporting (drill down looks nice), stronger authoring tools and easier version control, but is this worth the effort?
Idea 2: SQL Server Reporting Services and SharePoint 2010 with Access Services
The second idea is to kill Access as a database platform and migrate all our customers to SQL Server (we have hosted instances of our application for those customers who don't have the skill set to set up their own SQL Server instances). Once they're migrated we would use SQL Server Reporting Services as the reporting engine, with the ReportViewer control in server rendering mode.
In addition to SQL Server Reporting Services, I am curious as to whether SharePoint 2010 with Access Services could be used to rapidly migrate existing Access reports into a more manageable format. We'd take the Access report that the customer uses, convert it to an Access Web Report then make it available for them on a SharePoint site. This would only be for our hosted customers, but if we find a way to deal quickly massage the VBA out of customer reports we could churn through the several hundred custom reports our customers have.
I'm also interested in the ability to use an Access Web Navigation Form to act as a portal to all our reports. We'd host a web browser control inside our application which would give customers access to their own reports and to our standard suite.
We'd get all the benefits of Idea #1 plus the ability to write in full Transact SQL, a reports portal, and (hopefully) a reasonable upgrade path for customer's proprietary reports.
So, my question is: am I going about this the right way? Are these viable solutions for modern reporting systems, or laughable? We have a strong preference for using the ReportViewer control either in client rendering mode where our application processes the data, or in server rendering mode in conjunction with SQL Server - but are there reporting systems like Crystal Reports which offer better reporting and better migration paths for our legacy Access reports?
If you had up to 36 months of developer time, how would you do this?
Well, ok, no one else jumping in, I give this a go.
Quite interesting how you talking about a report writer that 15+ years old. Back then the Access report writer was beyond state of the art. It was a country mile ahead of everything else in the industry. Even today a lot of competing report writers don't have the concept of sub reports that allows modeling of relational data without having to resort to code or even SQL. Then, throw in programmable VBA, then the result is something that's very unique and powerful.
For access 2007, the report writer received some more nice upgrades in terms of layout controls but that going to be of little help here.
And, for 2010 we can now display reports in a sub-form control. This feature was added to facilitate use of the new access navigation control. Access 2010 has a new web browser control (works in forms or reports), and there also a new navigation control. Your post hints that the new navigation control and the web control are somehow related to each other but they completely different features.
Both the new web browser control, and navigation control can be used in both web appliations or 100% client only applications. The navigation control is nice since you can build that nav contorl by drag and dropping reports onto the nav control to build up a up a list of reports to choose from (it is slick and easy and nice). And with this navigation control, we can actually build some nice drill down type of interfaces for reports.
As you noted for access 2010 we now have web publishing of access reports and this feature is based on SQL server reporting services (they are RDL reports). However, two important issues here is no VBA is allowed inside of the web reports. And, I also point out that there is no automatic conversion utility that is built into access that will convert existing reports into web based reports. So to build a report that's going to be designated and published to the web, you have to choose specifically to create a web report to accomplish this goal. So this answers and clears up one question of yours of will this help you convert existing reports to SQL server, and the answer is no. So, Access will not help you convert existing reports to web based RDL reports (As noted, Access uses RDL and sql reporting for those web reports - those reports also render in the access client side without conversion).
Access has a great path for web based reports via SharePoint and also Access Web is coming to Office 365. However, keep in mind this ability is not going to help much with the existing reports that you have.
In fact one of the things I would be looking at if you're going to use winforms report viewer is the change in where that existing VBA report code will be moved to? You not really mentioned this issue. As noted one really interesting and great feature of those reports is that imbedded VBA code. Often that VBA will have been used because SQL and something like RDL will NOT work because neither of those languages (sql, and RDL) are procedural code.
I can't stress how important this concept is. So, this quite much means any report writer replacements means that code will now have to be OUTSIDE of the reports and moved into your application. So, keep this issue in mind as now when you issue new reports, you also be issuing new procedural code that NOT be contained in those reports. This code will have to become part of your application (so, to issue new reports, you will thus also be issusing a new version of your software).
You are not likely to find much that allows procedural code to be imbedded inside the report like you can with access. So, that report code and logic will now have to be built and maintained within your main application and outside of the reports.
At the end of the day, I should point out the old adage if it ain't broke, then don't change it. Access been around for a very long time, but we seen significant investments from the folks in Redmond into this product during the last few years, so it shows no signs of dying anytime soon.
So, one possible suggestion is to keep the status quo, and continue going the way it works now. I mean you stated that you have to continue supporting JET for this anyway so you not getting away from having to use a major part of Access anyway. So, you continue to have to use JET engine anyway. So, you just dumping the report side and you still have use the JET data engine anyway.
However, assuming this decision's been made, I can't really suggest what report writer you should replace the access one with. Obviously considerations for the next report writer should have a seamless path to web even if they are NOW going to be rendered on the desktop. It makes no sense to make a large investment today without web considerations in some fashion.
I do think SQL server reporting services is a good choice due to the web ability. And, as an access developer we also have the option to create web based reports but they also render perfect in the access client on the desktop side (and this works when you have no server and no conversion issues exist when publishing these reports to the web, or using them local on the client). So, even if you don't use access, do choose something that allows reports to render both desktop and web like access 2010 allows.
I would consider building the report system around some .net tools. This would likely not play too well as an embedded report system inside of your existing application, but it would allow you to issue new reports, and you would not have to touch your existing code base for each new report issued. This issuing of new reports that have procedural code needs to be resolved. You likely can now issue new reports without having to modify the main application because those reports can contain code inside. I would be looking to use something that would allow new reports to be built and issued but you not having to issue new edition of your main software. You might not embeed the code in the reports anymore, but you need to palce it somewhere, and hopefully outside of your main application.
Wow, this is a great question and Albert has given you a teriffic answer.
Unfortunately I do not believe there are any magic bullets to solve your problem. I have used Microsoft Access since it's first version, and always felt it's strongest feature was as a report generator, particulary when used with SQL Server. As you undoubtably know, one can often have issues with corrupted Access databases in a multi-user environment and SQL Server addresses that issue very nicely.
To my way of thinking the biggest problem with Access is that Microsoft brought out managed code (.Net) ten years ago now but Access is still a native application. In an ideal world Microsoft would rewrite Access in C# using all the latest features such as improved support for multiple processors etc. Unfortunately I do not expect this to happen any time soon.
Visual Basic for Applications (VBA) was definately far abead of "state of the art" when it was introduced, but today I believe most would agree that coding in VB.Net with Visual Studio is much more productive than continuing to develop in VBA.
SInce the selection of a new report generator is something you will need to live with for several years, perhaps it would be helpful to consider what an "ideal" report generator for the next ten years should look like?
Personally I would want:
1) All the great graphics and ease of skinning and branding that Silverlight provides.
2) Great multiprocessor support (you must have noticed how the UI thread in Access often appears "unresponsive" when running long queries or reports).
3) Support for lots of devices such as cellphones, iPads etc. While today the desktop and web dominate, these are becoming increasingly important (unless for some particular reason they are not important to your customers going forward).
4) Support for modern programming practices such as test driven development, dependency injection etc.
Please do let us know what you decide upon.
This is a long shot, but is there a possibility of using Access to generate a saved PDF and displaying that in your app in a PDF-viewing control that is part of your app, rather than external? Or export to XML or something (I haven't a clue what XML export options are available for reports in recent versions of Access, if any)?
The point is that you'd not have to rewrite the Access reporting logic, but you'd have eliminated the fake embedding and replaced it with something that's really embedded in your application.
What you'd be giving up is the perhaps the options that the Access UI gives the user, but I'm not sure how useful that is (I'd tend to not want those options available!).
Also, you'd be persisting the reports to disk, but I'm not sure this is much of any kind of significant issue, either, but it would entirely depend on the context (I'm assuming you have no 1000-page reports with heavy graphics, etc.).
You could take a look at ActiveReports by Data Dynamics. We use it within our apps for paperwork type reports (eg, invoices) and it's extremely flexible, far more so than what you can achieve with the MS reporting tools. For reports that are genuine reports rather than paperwork we use reporting services. It's been a while since I had to port an access report to active reports, but there is little or nothing you could do in access that you can't do in active reports. I'm also fairly certain that it has a decent tool for import access reports. There's a fully functional evaluation version available for download, which, unless they've changed things, just printes a watermark in the report footer rather than expires after a fixed evaluation period. Well worth a look, I'd say - Here's a link to their site
I won't get into any specifics since I'm not a Microsoft developer, but I can answer on how to integrate a legacy product into the current or new product. As for the 36-month question, see the end of this answer.
Usage Requirements - how do you intend to use the legacy code in the context of your new code?
Identify Use Cases - drill down into usage and create a use case for each transaction between the new and old code.
Identify I/O - drill down into each use case and identify I/O requirements
Write Tests - for each I/O pair, write tests to determine the best way to handle that I/O pair.
Reuse - reuse your tests to create a wrapper/API for the legacy code.
Future - as you replace legacy code with new code, let it match your wrapper/API so you can keep refactoring to a minimum.
If I had 36 months of development time to spend, I would spend 3-6 months writing a wrapper/API and then replace each unit tested I/O pair with new code every 7-10 days utilizing sprints (scrum/agile).
For the data store, I would absolutely move from Access to some SQL server product and prioritize that requirement for the new code.
I've used Crystal, Access (2 - 2007), SQL Reporting and now DevExpress and am very happy with DevExpress's reporting engine. It is specific to .net, but can be utilized by Windows Forms, ASP.net Web pages, WPF and Silverlight. If you are willing to utilize some .net controls, I highly recomend it. It can use just about anything as a datasource and is very flexible. My current projects aren't as complex as some things I have done in the past, but I would venture to say that I would rather do complex reports using the DX engine over any other I have used.
They have an End User designer that includes scripting capabiliities and DX is actively adding functionality.
I would recommend taking a look at: http://devexpress.com/Products/Index/Reporting.xml

Remote interop with OpenOffice Writer

I found some documentation about interop with OpenOffice using technologies like COM, but before delving in more deeply I wondered if anyone's worked on this kind of thing?
We have a need for the following, all wrapped up in a method call from a client PC (client talks to server using COM):
Client sends a map of name/value pairs to a server app
Server opens a Word template (.dot currently) file and looking up bookmarks using names from 1, replaces the text with values
Server saves file as a Word .doc file
We were doing this using Word but some changes in Windows 2008 mean if you run without a desktop/interactive-user, Word won't start. It's obviously a big hack but we're looking for a quick solution rather than re-engineering due to time constraints... so I wondered if we can simply run up OO Writer on the server to do the same job? I know how ugly it all is so don't really need suggestions to create a brand new C# open XML SDK application.
Multiple simultaneous requests can be ruled out as a potential problem (or at least it's never been a problem using Word so unless OO is different it'll be ignored).
If you are thinking OpenOffice might help, you could use JODReports or Docmosis to help, though you'd need a small Java program to bridge from your C++ app (cmd line or whatever). These tools will let you control OpenOffice a little easier for doing your merge task than working with the OO API directly (hopefully a lower learning curve).

Any way to display C++ on a webpage?

Is there a relatively easy way to display the output of a C++ program on a webpage? And I don't mean manually, in other words, you see it on a webpage as it runs not as in I make a code tag and write it in myself.
EDIT: Just so everybody can get this clear I am going to post this up here. I am NOT trying to make a webpage in C++. Please excuse me if this sounds spiteful or anything but I am getting a lot of answers relating to that.
Step one, get yourself a server-side language. Be that PHP, ASP, Python, Ruby, whatever. Get it set up so you can serve it.
Step two, find your language's exec equivalent. Practically all of them have them. It'll let you run a command as if it were from the command line, usually with arguments and capture the output. Here's PHP's:
http://php.net/manual/en/function.exec.php
Of course, if you're passing user-input as arguments, sanitise!
I've just seen that you accepted Scott's answer. I usually wouldn't chase up a SO thread so persistently but I fear you're about to make a mistake that you'll come to regret down the line. Giving direct access to your program and its own built-in server is a terrible idea for two reasons:
You waste a day implementing this built-in server and then getting it to persist and testing it
More importantly, you've just opened up another attack vector into your server. When it comes to security, keep it simple.
You're far better having your C++ app running behind another (mature) server side language as all the work is done for you and it can filter the input to keep things safe.
You could write a CGI app in C++, or you could use an existing web server language to execute the command and send the output to the client.
You want to use Witty.
Wt (pronounced 'witty') is a C++
library for developing interactive web
applications.
The API is widget-centric and similar
to desktop GUI APIs. To the developer,
it offers complete abstraction of any
web-specific implementation details,
including event handling, graphics
support, graceful degradation (or
progressive enhancement), and pretty
URLs.
Unlike many page-based frameworks, Wt
was designed for creating stateful
applications that are at the same time
highly interactive (leveraging
techinques such as AJAX to their
fullest) and accessible (supporting
plain HTML browsers), using automatic
graceful degradation or progressive
enhancement.
The library comes with an application
server that acts as a stand-alone web
server or integrates through FastCGI
with other web servers.
I am not sure this is what you are looking for but you may want CGI You may want to look at this SO question, C++ may not be the best language for what you want to do.
based off the questions you posted Writing a web app like what you want is no simple task. What I would recommend is use some other library (this is one i found with a quick google) to get a web console on your server and give the user it is running under execute deny permissions on every folder except the folder you have your app installed.
This is still is a risky method if you don't set up the security correctly but it is the easiest solution without digging around too much on existing libraries to just have the application interactive.
EDIT --
The "Best" solution is learn AJAX and have your program post its own pages with it but like I said, it will not be easy.
It sounds like you want something like a telnet session embedded in a webpage. A quick google turns up many Java telnet apps, though I'm not qualified to evaluate which would be most ideal to embed in html.
You would set up the login script on the host machine to run your c++ app and the user would interact with it through the shell window. Note though that this will only work for pure command line apps. If you want to use a GUI app in this way, then you should look into remote desktop software or VNC.
It may be worth looking into Adobe's "Alchemy" project on Adobe Labs
This may help you with what you're trying to achieve.
:)
Are you looking for something like what codepad.org does? I believe they explain how they did it here.
There is a library called C++ Server Pages - Poco. I used it for one of my college project, its pretty good. There is also good documentation to get started with, u can find it here http://pocoproject.org/docs/