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I have inherited a legacy app written in C++ (VS2003) MFC that was not updated in years.
I have limited experience in C++, being mainly a Delphi developer. All other apps of the company are written in Delphi.
Going forward, I see a few choices:
1) Keep the app as is and become a C++ MFC developer. But I don't like the idea of using an outdated technology (MFC) for years to come, trying to keep up with new Windows versions and UI standards. It somehow feels like making several steps backwards and I don't think this is the best way to go (?)
2) Convert the app to any modern UI technology offered with C++ and become a C++ developer, but at least using modern technology. Might be a lot of work, not sure.
3) Rebuild the app from scratch in Delphi, where I will be a lot more productive thinking about the future. It's a lot more work right now, but it might pay off later.
Obviously, I personally prefer 3) but I would like to know from your experience which way is the best for the product.
It's a long term decision to make and I will have to stick with it, therefore I don't want to rush into one direction.
(I have intentionally not tagged this question as C++, trying to get answers from Delphi developers in similar situations)
EDIT:
Thanks to all for your answers.
After learning that it is possible to switch to C++ Builder with a MFC application, this seems to be the best solution.
It combines the least amount of modifications to the current app with the possibility to go forward using the VCL for future GUI improvements.
EDIT2:
It's not possible to combine MFC and VCL in one app, therefore C++ Builder won't be an option. (thanks David for pointing this out)
In general everything depends on how complex the application's logic is and what is the projected life time of the application. If it requires maintenance for another 20 years, then
I'd rewrite the UI in Delphi and move the business logic into C++ DLL (for beginning and possibly rewrite it in Delphi either). Then it can turn that the application can be maintained this way for another 10 years and relatively easily ported to other platforms if needed (less work would be required).
This is a hard question to answer generically. Can you provide any more information about your specific app? What sort of technologies does it use? How separated is the UI from underlying layers and logic?
Some general-ish points though:
Rewriting an app is generally a bad idea, for the following reasons:
It's surprisingly hard to get an accurate idea of the requirements. You're sure you know what it does (after all, it's right there in front of you!), but then you release your rewritten app and you get complains that functionality you didn't know was there is missing, that functionality is harder to access if you've changed something, etc.
It introduces bugs. The code, especially if it's old, is full of bugfixes, tweaks, etc. You will lose all that if you rewrite, especially if it's a different language and you can't reuse any code at all.
When using a different UI layer (MFC to something else) separating the UI can be very hard if the app wasn't written well in the first place. You will probably end up doing a lot of refactoring, even if you don't do a complete rewrite and simply move from MFC to 'something else'.
MFC is kept up to date (ish) - there is a MFC Ribbon control, for example, as well as modern controls and Windows 7 support. The least amount of work, probably, would be to upgrade to a modern version of Visual C++ and become a C++ developer. However, you're quite right that MFC is an old technology and is unpleasant to use, not only because of its design, but also because modern form designers etc are great to use.
You're a Delphi developer. Without rewriting the entire thing, you could consider migrating to C++Builder. Consider this:
You can use old versions of MFC with C++Builder. I've never done this, since the VCL is miles ahead, but it's possible and there are a number of people who do it. Check out this forum, for example. (Credit for that link: this thread.)
Once you have your app compiling and working with C++Builder, you can start migrating to the VCL. As a Delphi developer you'll find using this, even with C++, very familiar. It's the same form designer of course, and using it from C++ is pretty simple - it's a different language but code is often line-for-line translatable. Everything you're used to (DFM files, units, event handlers, etc) all translate.
Not only that, but Delphi code can be used in C++ projects. Just add the units to the project, and in your C++ code include the auto-generated unitname.hpp file. You can't (easily) use C++ code from Delphi, but you could create new modules in Delphi and use them from C++. As you do this, more and more of your app will slowly become Delphi code - ie, you don't need to rewrite in a different language all in one go.
As a Delphi developer, I'd suggest going the C++Builder route. Get it working with MFC, and then migrate your windows to the VCL. At that point, you could start rewriting modules in Delphi, or you may find yourself comfortable enough in C++ to continue developing as is.
Edit: I noticed in a reply above you like the idea above of making it a C++ DLL. The link I gave a paragraph or two above of using C++ object from Delphi might be more applicable than I thought. It would fit the RAD Studio (mix of C++ and Delphi) method as well.
Keeping the app as is, tying you to MFC, is likely not very productive - You'll need to learn a GUI toolkit you'll most likely never use for something else (Delphi is great for GUI, MFC doesn't even come close IMO), in addition to a new language.
That leaves you with the choice of rewriting it in a somewhat unfamiliar language using an unfamiliar GUI toolkit, which'll take a lot more time than rewriting it in a familiar language using a familiar GUI toolkit. So you should just get started porting this to Delphi.
Rewriting C++ code in Delphi isn't as easy as you think. A better way to rewrite it is by just redesigning it from scratch, without looking at the old code. Feel free to look how the old application worked, so you can rebuild it. Just don't look at the code. That way, you should get a more modern result.
Of course, if you use the RAD Studio then you have both the C++ as Delphi compiler, thus it should be able to continue to develop the C++ application, although this means you have to learn C++. Then again, any good programmer should be able to just move to another programming language and learn to use it within 2 weeks to a month. C++ can be complex but still, learning C++ and then maintaining the legacy app should take a lot less time than a complete rewrite.
Do keep in mind that any generic C++ application should be able to be compiled for any platform, although the MFC will probably restrict this to just Windows. Still, it's a language that has an even better backwards compatibility than Delphi!
But to keep in mind, will this app run on a different platform in the future? Should it become a .NET application? Or run on Linux? Should it support tablet computers? Android? Your choices today might be outdated again in two years. And since Delphi has a bit uncertain future right now, mostly because C#/.NET became so popular, you might have a more safe bet with C++. Try to replace the MFC libraries with a more modern UI technology, preferably one that's available for multiple platforms, and think very, very well about the future usages of this application.
In general I'd say:
If it's a tiny tool application, and it takes just a couple of days to do a full rewrite: go for it. Don't waste your time creating dll wrappers or to interface with the existing code in other ways. Just do a full rewrite and be done with it.
Otherwise: you'll probably be making changes in one specific area of the application at the time only. Unless the code is a complete spaghetti, you could even get away with making some local changes without fully understanding the implementation details of the rest of the code.
In any case, you need to invest some time into understanding the application and its language + frameworks.
You have a great opportunity to learn C++ and MFC. Take advantage of it. When Delphi goes astray you will have the required knowledge to keep on coding with a language that won't go away so easily, and you can even broaden your development horizons to areas Delphi (and C++ Builder) will never reach. MFC is no more outdated than the VCL is (although I agree the original design is worse).
Good UI programming has nothing to do with the ability to drop controls on a form visually. Many great applications are not built that way. Actually, trying to rewrite it in Delphi could bring you issue in the future, as long as Embarcadero delivers slowly, and without a credible roadmap.
I recommend
1) Keep the app as is and become a C++ MFC developer. But I don't like the idea of using an outdated technology (MFC) for years to come, trying to keep up with new Windows versions and UI standards. It somehow feels like making several steps backwards and I don't think this is the best way to go (?)
Since MFC is well supported and keeps going with the time. MFC is also a what-you'd-call intrusive framework, meaning that the framework dependencies are usually not easily refactored. (The author of CPPDepend published some nice stats on that IIRC, but I can certainly vouch for this from my own experience with large MFC applications).
If you're gonna rewrite to any modern UI framework, don't code the UI in C++ (judging from the fact that Delphi is an option, it is not about realtime visualizations or something like that).
(I'll unask the unasked question here: I you're gonna rewrite, XXXXXXXXXXXXX?) please gentle(wo)men, let's not do the flame
Does the app come with a descent amount of automated tests? If not you're pretty much stuck with option 1 and hope for the best. If there are many tests you can do a lot more with the code without breaking all kinds of things you didn't know were there.
Most web frameworks are still using the traditional action based MVC model. A controller recieves the request, calls the model and delegates rendering to a template. That is what Rails, Grails, Struts, Spring MVC ... are doing.
The other category, the component based frameworks like Wicket, Tapestry, JSF, or ASP.Net Web Forms have become more popular over the last years, but my perception is that the traditional action based approach is far more popular. And even ASP .Net Web Forms has become a sibling name ASP .Net Web MVC. Edit: Maybe my perception was wrong because of the impression of increasing interest in Wicket. If I ask Google Trends, there is much more growth in the tradional MVC frameworks.
I think the kind of applications built with both types of frameworks is overlapping very much, so the question is: Why are action based frameworks so predominant?
the component based frameworks like
Wicket, Tapestry, JSF, or ASP.Net Web
Forms have become more popular over
the last years
[Citation Needed]?
I seriously doubt this claim. MVC has taken over the .Net blog/twitter sphere. Its really hard to find somebody saying "we'll use webforms for our next project".
MVC fits the stateless nature of the web better. Component frameworks are an abstraction web developers didn't want.
Why are things more popular? They are several reasons: because of a good user experience, fast development cycle, cheapest things, etc
But sometimes
the loudest
or most hyped (rails, although it is great ;-))
or most arrogant (apple)
or the things with the most aggressive marketing (microsoft)
will win.
That is called evolution.
BTW: I am with Thevs. The component based frameworks will be the final winners (like GWT/Vaadin or wicket).
Inertia. Once you've invested a lot in one technology, it becomes progressively more difficult to change to something better. And it is not 10 times better, because then everyone (even the CEO) would have seen the change is needed.
I believe it's because action-based frameworks give developers (and designers) more control over the appearance of the page. Component-based frameworks try (unsuccessfully, IMHO) to hide the fact that the web is the web. They try to make web programming something like programming a native desktop widget toolkit like WinForms or Cocoa.
But the web is very, very different from that. I think action-based frameworks are popular because they recognize this.
EDIT
Apparently some people have misunderstood what I mean by this, so let me be clear. I'm NOT criticizing web application that appears to users to function like a desktop application. I have absolutely no problem with that.
What I'm talking about is the underlying coding methodology and philosophy. Each tag in a tag library system renders HTML in a certain way, analogous to a widget in a desktop programming library like Cocoa or WinForms. Some systems allow you to customize the rendered HTML, but this can sometimes be non-trivial to accomplish. It will render CSS classes and so on over which you either have little control or have to make a special effort to control. It pretends to be a black-box solution, but it cannot possibly be, because if you want to style the rendered HTML or target it with JavaScript, you have to understand its structure and so on.
I suspect that developers are using MVC frameworks as a simple way of exposing services, not as action-based web app frameworks (this is pure speculation on my part). i.e. they are using them for AJAX requests. I would predict that the concept of action-based frameworks quietly goes away over the next couple of years, along with (to some extent) the concept of MVC in this context.
I think you only see these frameworks showing all around. But most programmers use in-house (custom) or much more simple framework models (like ExtJS or JQuery) and silently do their job.
EDIT: By the way, I think MVC model is trying to mimc the old and probably obsolete business/presentation separation model which was proposed for legacy applications some time ago.
I see no future for this model (2-3 years from now). AJAX is already changing all the way you're working with backend.
As an Asp.Net MVC developer, what is the best starting point to dive into WPF?
WPF is a totally different technology used for a different purpose. You're writing desktop applications rather than web applications.
While there is some cross over in terms of design patterns and both use C# (or VB.NET) as the "code behind", they each need their own approach.
Your best bet is to read and work through some WPF tutorials and then decide on a fairly simple application to write from scratch. Get that working and you'll have a reasonable grounding in the technology.
WPF is a platform for developing Windows Application , while ASP.NET MVC is a platform for developing Web Applications.
If you are into Web apps development, and you want to learning something similar to WPF, you can go for Silverlight.
Silverlight is Rich Internet Application development (RIA) platform that can be used to develop interative web apps. Silverlight is also capable of running on desktop as Out of Browser Application.
I suggested Silverlight because, Silverlight & WPF both share a markup language called XAML to a great extent. Once you are familiar with XAML, you can slowly start with WPF.
WPF consists of wide range of new terminologies and techniques such as :
Routed Events
Data Binding
Commands
Styles and Templates
Some of these are present in Silverlight while some are yet to be introduced in future versions Silverlight.
If you're looking for a framework that helps you apply some 'best practices' in WPF/Silverlight development (similar to MVC helping you in the ASP.Net world), you may want to have a look at caliburn and/or prism (aka. CompositeWPF). However, as others have stated, it's probably a good idea to learn some of the basics of WPF first.
Since asp.net mvc did away with many controls that were in webforms, does this make rapid application development equal with other environments now? For example, if I have an mvc framework in php, j2ee, etc., and I have asp.net mvc, and the coder knows the given platform, isn't the development advantage gone in visual studio?
If I am wrong about controls being missing please let me know, it was my impression they were (and I couldn't use them when I tried it last.)
I ask because where I work some like Microsoft - a lot, some can live with it, but the ones that like it point to Visual Studio for rapid development. I thought much of that was gone with asp.net mvc 1.0.
EDIT: I guess I am thinking that dragging and dropping controls means Rapid Application Development (again, assuming the coder knows what they are doing everywhere else.)
Rapid application development is just a buzzword. It exists if you develop an application rapidly, not due to any particular tool or technology.
ASP.NET MVC is just a different approach. Some people can work faster when they are closer to the HTML. For me, this means I don't have to deal with the (IMHO) touchy databinding model of WebForms. Instead, I pass my Model directly to my View for rendering. That lets me develop rapidly. You can still develop your own UserControls (or download many of the ones that are available through open source projects), but you can't use anything that has events or ViewState intrinsic to it.
EDIT: RAD is also a subjective term. Is it rapid application development if you can churn out the first iteration in two weeks, but have to push the schedule back two months for the second iteration because the code was not maintainable?
If you are talking about the ability to drag controls onto a page, click them, set some properties, and have a code generated for you, and a working application by basically dragging controls and tools around, yes, MVC removes the ability to do RAD.
MVC exists to solve a different problem. It is for people that want separation of concerns to support unit testing and extensibility. Things that were nearly impossible to get with classically developed asp.net applications.
Web forms was an attempt to be more RAD if you will. However, the emergence of things like MVC, and Dynamic Data and things like Linq and Linq2SQL are pretty darn good evidence that Web Forms alone were not the panacea RAD platform.
From a personal standpoint, one may be faster at Web forms just by experience. That doesn't mean the platform or it's competitors are better or worse at RAD.
A lot of people found that Web Forms took so much control away and had such large event models that it ended up being less RAD than hoped.
I'd say that Rapid Development and ASP.NET MVC are not mutually exclusive per se. however since MVC has the intent of segregation of responsibility to (amongst others) allow testability, it might not be the best choice for Rapid Development-
On the otherside are ASP.NET Webforms where you can do ALOT "visually"/using drag-n-drop (i.e. no code), which to some extent does a very good job of for example preventing testability. But developing is a "no-brainer" - meant in the most positive way :)
Well, I've never considered Visual Studio as a RAD platform. Faster than PHP, sure. Comparable to Netbeans/Eclipse. Not even close to a true RAD platform though (oh Delphi, how I miss thee!).
Simple as it is :
Why to move to Asp.NET MVC & why not to move ( if there is any reason ) ?
Added
Is it a necessity to move ?
Can we say the future belongs to asp.net mvc ?
How many years do you think it can stays on top ?
MVC is much more well constructed, allowes for much better code seperation and control over markup, and is much lighter on the server, that IMHO the only reason not to move is if you have a legacy .NET application (or other) that is working flawlessly, and you're not expected to perform serious adjustments / fixes on it in the near future.
If you do decide to move, you should know that you'll be able to reuse very little of your webforms GUI and user controls, since MVS is built a bit differently. You class libraries you could reuse, if they're written well. In any case, writing stuff in MVC is much faster than in WebForms, even if done from scratch.
also looking at moving at the moment.
the main bonus for me is the complete control over layout. i'm also looking into implementing a restful API which the MVC model works very nicely with because of the path structure.
Josh
If we move for MVC we can add or edit any module so easyly.
So we can add any new module just like a plugin
I patrially disagree with the accepted answer. I have built large applications in both WebForms and MVC and here is my opinion:
ASP.Net Web Forms and ASP.Net MVC are both great frameworks that allow the C#/VB Net developer to build enterprise level applications. Choosing which one to use for your app depends on a few factors. The MVC model has been around for many years, it is well suited if you need more fine-tuned control over the page cycle process and it is also superior when it comes to unit testing etc, because it supports true separation of business logic and presentation layers.
However, do not dismiss Web Forms, the reality is you can continue to use the web forms framework and still have tight control over your page elements be simply moving away from pre-built server controls and integrating HTML5 standard controls. You can take advantage of new JavaScript frameworks like jQuery, you can improve search engine friendliness by using techniques like URL Re-Write, and you can reduce or eliminate post-backs by taking advantage of asynchronous frameworks like jQuery AJAX and SignalR.
The main reason I disagree with the accepted answer is the statement "writing stuff in MVC is much faster than in WebForms" is completely inaccurate. As any developer who has actually built MVC apps will tell you, it's actually much fast to build WebForms apps. The reason is not just learning curve, but the fact that while MVC gives you the benefit of "under-the-hood" access to the page cycle and more direct access to HTML output, is also the reason it takes longer to build MVC apps. Trust me, you will find yourself doing much more "plumbing" work than you ever did with "drag-and-drop" WebForms development.
The fact is, there was a lot of hype when ASP.Net MVC first came out and too many developers assumed it was a replacement for Web Forms. It hasn't. As I stated in the beginningm both frameworks are great, they both have their pros and cons. I would guess that 90% of developers are still building new apps in WebForms.
That's my 2c.