Recently I was talking with a friend of mine who had started a C++ class a couple months ago (his first exposure to programming). We got onto the topic of C# and .NET generally, and he made the point to me that he felt it was 'doomed' for all of the commonly-cited issues (low speed, breakable bytecode, etc). I agreed with him on all those issues, but I held back in saying it was doomed, only because I felt that, in time, languages like C# could instead become native code (if Microsoft so chose to change the implementation of .NET from a bytecode, JIT runtime environemnent to one which compiles directly to native code like your C++ program does).
My question is, am I out to lunch here? I mean, it may take a lot of work (and may break too many things), but there isn't some type of magical barrier which prevents C# code from being compiled natively (if one wanted to do it), right? There was a time where C++ was considered a very high-level language (which it still is, but not as much as in the past) yet now it's the bedrock (along with C) for Microsoft's native APIs. The idea that .NET could one day be on the same level as C++ in that respect seems only to be a matter of time and effort to me, not some fundamental flaw in the design of the language.
EDIT: I should add that if native compilation of .NET is possible, why does Microsoft choose not to go that route? Why have they chosen the JIT bytecode path?
Java uses bytecode. C#, while it uses IL as an intermediate step, has always compiled to native code. IL is never directly interpreted for execution as Java bytecode is. You can even pre-compile the IL before distribution, if you really want to (hint: performance is normally better in the long run if you don't).
The idea that C# is slow is laughable. Some of the winforms components are slow, but if you know what you're doing C# itself is a very speedy language. In this day and age it generally comes down to the algorithm anyway; language choice won't help you if you implement a bad bubble sort. If C# helps you use more efficient algorithms from a higher level (and in my experience it generally does) that will trump any of the other speed concerns.
Based on your edit, I also want to explain the (typical) compilation path again.
C# is compiled to IL. This IL is distributed to local machines. A user runs the program, and that program is then JIT-compiled to native code for that machine once. The next time the user runs the program on that machine they're running a fully-native app. There is also a JIT optimizer that can muddy things a bit, but that's the general picture.
The reason you do it this way is to allow individual machines to make compile-time optimizations appropriate to that machine. You end up with faster code on average than if you distributed the same fully-compiled app to everyone.
Regarding decompilation:
The first thing to note is that you can pre-compile to native code before distribution if you really want to. At this point you're close to the same level as if you had distributed a native app. However, that won't stop a determined individual.
It also largely misunderstands the economics at play. Yes, someone might perhaps reverse-engineer your work. But this assumes that all the value of the app is in the technology. It's very common for a programmer to over-value the code, and undervalue the execution of the product: interface design, marketing, connecting with users, and on-going innovation. If you do all of that right, a little extra competition will help you as much as it hurts by building up demand in your market. If you do it wrong, hiding your algorithm won't save you.
If you're more worried about your app showing up on warez sites, you're even more misguided. It'll show up there anyway. A much better strategy is to engage those users.
At the moment, the biggest impediment to adoption (imo) is that the framework redistributable has become mammoth in size. Hopefully they'll address that in a relatively near release.
Are you suggesting that the fact that C# is managed code is a design flaw??
C# can be natively compiled using tool such as NGEN, and the MONO (open source .net framework) team has developed full AOT (ahead of time) compilation which allows c# to run on the IPhone. However, full compilation is culbersome because it destroys cross-platform compatibility, and some machine-specific optimizations cannot be done. However, it is also important to note that .net is not an interpreted language, but a JIT (just in time) compiled language, which means it runs natively on the machine.
dude, fyi, you can always compile your c# assemblies into native image using ngen.exe
and are you suggesting .net is flawed design? it was .net which brought back ms back into the game from their crappy vb 5, vb 6, com days. it was one of their biggest bets
java does the same stuff - so are you suggesting java too is a mistake?
reg. big vendors - please note .net has been hugely hugely successful across companies of all sizes (except for those open source guys - nothing wrong with that). all these companies have made significant amount of investments into the .net framework.
and to compare c# speed with c++ is a crazy idea according to me. does c++ give u managed environment along with a world class powerful framework?
and you can always obfuscate your assemblies if you are so paranoid about decompilation
its not about c++ v/s c#, managed v/s unmanaged. both are equally good and equally powerful in their own domains
C# could be natively compiled but it is unlikely the base class library will ever go there. On the flip side, I really don't see much advantage to moving beyond JIT.
It certainly could, but the real question is why? I mean, sure, it can be slow(er), but most of the time any major differences in performance come down to design problems (wrong algorithms, thread contention, hogging resources, etc.) rather than issues with the language. As for the "breakable" bytecode, it doesn't really seem to be a huge concern of most companies, considering adoption rates.
What it really comes down to is, what's the best tool for the job? For some, it's C++; for others, Java; for others, C#, or Python, or Erlang.
Doomed? Because of supposed performance issues?
How about comparing the price of:
programmer's hour
hardware components
If you have performance issues with applications, it's much cheaper to just buy yourself better hardware, compared to the benefits you loose in switching from a higher-abstraction language to a lower one (and I don't have anything against C++, I've been a C++ developer for a long time).
How about comparing maintenance problems when trying to find memory leaks in C++ code compared to garbage-collected C# code?
"Hardware is Cheap, Programmers are Expensive": http://www.codinghorror.com/blog/archives/001198.html
Related
Why do Actionscript, Java, C#, etc. compile into intermediate code?
I'm aware of cross-platform benefits of using intermediate code.
The question is: What is the benefit of compiling to intermediate code, compared to scripts (JS, Python, PHP, Perl, etc.) that are interpreted?
Is it just for code obfuscation? Or what?
In addition what is the benefit compared to compiling to native code?
It is much faster to parse and JIT-compile IL code than to parse a high-level language like Java or especially C# (which has more features).
It also allows developers to use new language features without updating anything on the end-users' machines. (eg, LINQBridge)
First of all historically java was targeted to mobiles and embedded devices with very limited CPU/memory, and JVM on such devices can't do any intensive optimization, like modern JITs do for now. So java engeneers decided to move optimization to compile phase.
Next, having "byte code"/IL allows you to have many compilers from different languages into such byte code - and only one JVM/JIT. It is much more efficient then to create separate VM+JIT for each language. Remember, you have Java, JRuby, JPython, Groovy, etc... in JVM world, and C#, VB#, ASP.NET, F#, etc -- in .NET world, and only one runtime/VM for each.
Intermediate code is very similar to assembly in that it contains a limited set of instructions. The runtime is then able to reliably and consistently operate on this (somewhat) small set of instructions without having to worry about parsing the language, etc. It can therefore gain performance improvements and make optimizations.
In .NET compilation to MSIL solves interoperability between different languages like C#, VB.NET etc.
Binary code instructions are very simple and atomic, much more so than programming statements can be.
For example, z = a + b - (c * d) would need to be translated into loading four values into registers, then an add, multiply, and subtract, then write into another memory location. So we have at least 8 instructions or so just for that line!
Intermediate code is the best of both worlds-- cross-platform, but also closer to the way machine code is normally written.
In addition to SLaks's answer, compiling to IL enables a degree of cross-language interoperability that generally doesn't exist in interpreted languages.
This advantage can be huge for new languages. Scala's only been around since 2003, and it's already gained an immense amount of traction. Ruby, on the other hand, hasn't spread very far beyond being used for Rails apps in its 1.5 decades of existence. This is at least in part because Scala is bytecode-compatible with all pre-existing Java code and libraries, which gives it a huge leg up: Its community can focus most of its effort on the language itself, and potential adopters don't have to worry about going through any special contortions (or, worse yet, replacing their entire codebase) in order to start using Scala. F#'s story is almost identical, but for the other major managed environment.
Meanwhile Ruby doesn't speak with code from other languages quite so easily, so its community has to sink a lot more effort into developing Ruby-specific libraries and frameworks, and its potential users have to be a lot more willing to commit to a large-scale platform shift in order to use it.
Good afternoon,
I thought about writing an application which I may or may not commercialize, depending on how good the final application is. It is like a personal project, with which I hope to learn many more things about programming, for currently I only know most about C and C#. That's why I thought about starting this project as an unmanaged C++ Win32 application. The problem is that it is most dificult to even show a simple window when compared to C#...
How many people/companies use the Win32 API & C++ in today's business world? How does it perform in comparison with C#?
The application in question may eventually be an IDE for a specific language but whith features like command recognition and spell checking already built in.
Thank you very much.
It seems that when performance is needed people are willing to give up C# for C++.
Have a look at this "success" story Lessons from Evernote’s flight from .NET.
On our test hardware, Evernote 4
starts five times faster, and uses
half the memory of Evernote 3.5.
Evernote chose WTL and Chromium Embedded Framework. Basically they've reused Google's Chrome in their application.
For your first project and w/o prior C++ and Win32 experience, I would STRONGLY recommend you use the C# , as it will be easier for you to get something done thereby gaining confidence and skill as you go.
I'm a huge fan of C++ under windows, I've been doing it most of my adult life. That said, if you have no experience of C++, and you want to write a windows application, I'd suggest going with the C# route under .NET. Whilst I love native C++, I really disliked C++/CLI, and the horrid ^ suffix for references.
Given this is a personal project, I wouldn't worry too much about whether businesses use C++ or C#, but I will say that it is easier to find a C# developer these days than it is a C++ developer. And no, I am not favouring one language over the other here, it just appears to be the reality (at least in my experience). As for C++/CLI developers? They're kind of thin on the ground :)
You'll definitely be up and running faster with C# than you would with Visual C++/MFC/some-other-gui, but remember there are certain things you may not be able to do in C# (and have to import the native win32 calls via DllImport), but I doubt you'll come across these fringe cases just yet.
C# is the easy route, and the route most-often pushed by Microsoft. What they don't tell you, though, is that all of their headline products (parts of Visual Studio excepted) are written in C/C++. I'd say, in fact, that most major software packages you are familiar with are written in C/C++.
I'd go with c# too, as it is far more common in a business world (on GUI side at least), than unmanaged c++/win32. You'll also get your desired results faster, especially if you don't know c++.
On the other hand, c++ performs better (if written properly) - so if you are planning some intensive work in your app - maybe c# just won't handle it (but I strongly doubt this is the case).
At last, but not the least - if you are planning for clients, that for some reason do not have and can not get .NET framework (or any other framework, i.e. Java) - then native code is your only solution.
I have only been using C++ for quite a few years, but I have never had to write any programs which required a User Interface. When I did, I tried to learn to use Qt, but found it to be somewhat of a pain and eventually gave up. I recently just started taking a class on C# .NET and in the first week I have already started developing a pretty advanced application for my companies billing system.
If you were already a seasoned C++ veteran and preferred it over C# .NET, then I would say by all means go for it. In this case however, I would strongly recommend you go with C# .NET for quite a few reasons.
1) The time is takes to do something in C# will probably be at the very least about 10x faster than doing it in C++ regardless of the API you used.
2) The learning curve of C++ on top of already trying to write an application with a UI (which is already very difficult in C++) will make this take an extremely long time.
What can be done in VC++ (native) that can't be done with VC#?
From what I can tell the only thing worth using VC++ native for is when you need to manage memory yourself instead of the CLR garbage collector, which I haven't seen a purpose in doing either (but thats for another question to be asked later).
Cross-platform development. Yes Mono exists, and Java's somewhat more predictable to have it function EXACTLY the same on more platforms, you can find a C/C++ compiler for just about any platform out there, where you can't with C#.
Also linking into 3rd-party libraries, while I'm sure there's a way to leverage them in C#, you'll be able to take advantage of them without interop (Marshaling, etc) in C++.
Edit: one last thing: RELIABLE memory management. Yes you can use dispose(), and try-finally, but there's nothing quite like KNOWING the memory is gone when it's popped off of the stack. Through techniques like RAII, when you use well-constructed classes, you will KNOW when your classes release resources, and not waiting around for the GC to happen.
With P/Invoke there is very little that is impossible in .NET (most obviously device drivers).
There are also things where the advice is to not use .NET (e.g. shell extensions, which get loaded into any process that opens a file dialogue1).
Finally there are things which will be much harder in .NET, if possible at all (e.g. creating a COM component that aggregates the FTM).
1 This can create a problem if that process is already using a different version of .NET. This should be alleviated in the future with .NET 4 having the ability to support side by side instances of the runtime.
I'm not sure if you're talking about language features or applications. My answer though is for applications / components.
Really there are only 2 things you cannot do in C# that you can do in C++.
You cannot use C#, or any other .Net language, to write a component for a system that only accepts native components
You cannot use C#, or any other .Net language, to alter certain properties of a CCW for which the CLR does not allow customization
The most notable item here is Device Drivers. This is a framework that only accepts native components and there is no way to plug in a managed component.
For everything else it's possible to do the same thing in C# as it is in C++. There are just a lot of cases where you simply don't want to and a native solution is better. It's possible for instance to manage and manipulate memory in C# via unsafe code or IntPtr. It's just not nearly as easy and generally there's no reason.
You can't write device drivers for one.
I think there are several important points:
You can do anything in C#/C++/Java/Python/Lisp or almost any other language, finally all of them Turing complete ;)... The question is it suits your needs?
There is one big and extreamly important limitation of C#... It runs only one single platform Windows... (Mono is still not mature enough).
There are many applications where GC is just a waste of resources, applications that can't afford you throw up 1/2 of memory untill next gc cycle: Games, Data Bases, Video auido Processing and many other mission critical applications.
Real Time applications (again games, video processing and so on). Non-deterministic GC makes life much harder for them.
In fact, most of desktop applications: Web Browsers, Word Processors, Desktop Environment itself (like Windows Explorer, KDE or Gnome) are written in compiled languages with careful thinking about resources... Otherwise, they would just be terrible bloated applications.
Whereas writing shell extensions in Windows XP was possible in C# it is next to impossible to write shell extensions for Vista and Windows 7. Shell extensions and Namespace extensions (and anything else that uses the new Properties system) (kindof) must be done in C++ unless you're into pain.
There are two obvious answers:
VC# can never run without the .NET
framework. Native C++ can. That may
be necessary in some areas (others
have mentioned device drivers, but
more common examples might simply be
clients where the .NET framework is
not installed. Perhaps you're
distributing an application and you
know not all of your customers are
willing to install .NET, so your
sales would go up if you made an app
that just worked without the
dependency on .NET. Or perhaps you're
working on some mobile device where
the couple of megabytes taken up by
the .NET CF can not be justified. Or shell extensions where using .NET can cause nasty problem for the user.
And VC# can never use C++ language
features. Native C++ can. (Managed
C++ can too, of course, but that's a
different issue). There are, believe it or not, things that can be done more conveniently or elegantly in C++. And they're only accessible if you're programming in C++.
System calls are no problem, however. p/invoke lets you do those from C#, almost as easily as you could from C++.
inline assembler
You cannot use C++-Libraries with classes (P/Invoke can only be used for functions AFAIK)
You cannot use callbacks with P/Invoke.
Is C# in particular and .NET in general self compiling yet (this is not a troll, I genuinely don't know)? If not, you can use VC++ to write C# and .NET, but you can't use C# to do the same job.
This is tongue in cheek, but it also is an answer to your question... you can screw things up much more severely in VC++ than you can in VC#. Not that you can't manage to screw things up severely in VC#, but in general, you can screw them up easier and more thoroughly in VC++.
Again, kind of tongue in cheek, but also an answer to your question. Perhaps not what you were hoping for, but... :-)
There's also hard real-time applications. Any language with a GC cannot be used, just in case it decides to collect during a time-constrained part of the code. Java was notorious for not even allowing you to try (hence the EULA about not using it for software "intended for use in the design, construction, operation or maintenance of any nuclear facility"
(yes, I know they've since made a modified version of Java for real time systems).
For example, it makes sense to use C++ if it's harder to translate the header files for existing libraries than it is to give up the existing managed libraries.
The Main difference is:
C++ is a core language with which you can build stand-alone programs. These Programs communicate directly with the the operating system and nothing else. C++ compilers exist for more or less all platforms (operating systems).
C# is a language that conforms to the CLS. A program written in C# can not start without a CLI engine (.NET Framework, Mono, etc.). A Program written in C# communicates with the .NET framework AND with the operating system. You have a man in the middle. Like all servicing personal, this man can help but it will cause additional trouble. If you want to port, you have a different man in the middle etc. CLI Implementations do not exist for all platforms.
By my opinion every additional framework is a additional source of problems.
Using SSE instructions seems to be one of these cases. Some .NET runtimes will use some SSE instructions, depending on your code. But in VC++, you can use the SSE intrinsics directly. So, if you're writing a multimedia code, you'd probably want C++. (C++/CLI might work as well, presumably)
I learned Java in college, and then I was hired by a C# shop and have used that ever since. I spent my first week realizing that the two languages were almost identical, and the next two months figuring out the little differences. For the most part, was I noticing the things that Java had that C# doesn't, and thus was mostly frustrated. (example: enum types which are full-fledged classes, not just integers with a fresh coat of paint) I have since come to appreciate the C# world, but I can't say I knew Java well enough to really contrast the two so I'm curious to get a community cross-section.
What are the relative merits and weaknesses of C# and Java? This includes everything from language structure to available IDEs and server software.
Comparing and contrasting the languages between the two can be quite difficult, as in many ways it is the associated libraries that you use in association with the language that best showcases the various advantages of one of another.
So I'll try to list out as many things I can remember or that have already been posted and note who I think has the advantage:
GUI development (thick or thin). C# combined with .NET is currently the better choice.
Automated data source binding. C# has a strong lead with LINQ, also a wealth of 3rd part libraries also gives the edge
SQL connections. Java
Auto-boxing. Both languages provide it, but C# Properties provides a better design for it in regards to setters and getters
Annotation/Attributes. C# attributes are a stronger and clear implementation
Memory management - Java VM in all the testing I have done is far superior to CLR
Garbage collection - Java is another clear winner here. Unmanaged code with the C#/.NET framework makes this a nightmare, especially when working with GUI's.
Generics - I believe the two languages are basically tied here... I've seen good points showing either side being better. My gut feeling is that Java is better, but nothing logic to base it on. Also I've used C# generics ALLOT and Java generics only a few times...
Enumerations. Java all the way, C# implementation is borked as far as I'm concerned.
XML - Toss up here. The XML and serialization capabilities you get with .NET natively beats what you get with eclipse/Java out of the box. But there are lots of libraries for both products to help with XML... I've tried a few and was never really happy with any of them. I've stuck with native C# XML combined with some custom libraries I made on my own and I'm used to it, so hard to give this a far comparison at this point...
IDE - Eclipse is better than Visual Studio for non-GUI work. So Java wins for non-GUI and Visual Studio wins for GUI...
Those are all the items I can't think off for the moment... I'm sure you can literally pick hundreds of items to compare and contrasting the two. Hopefully this lists is a cross section of the more commonly used features...
One difference is that C# can work with Windows better. The downside of this is that it doesn't work well with anything but Windows (except maybe with Mono, which I haven't tried).
Another thing to keep in mind, you may also want to compare their respective VMs.
Comparing the CLR and Java VM will give you another way to differentiate between the two.
For example, if doing heavy multithreading, the Java VM has a stronger memory model than the CLR (.NET's equivalent).
C# has a better GUI with WPF, something that Java has traditionally been poor at.
C# has LINQ which is quite good.
Otherwise the 2 are practically the same - how do you think they created such a large class library so quickly when .NET first came out? Things have changed slightly since then, but fundamentally, C# could be called MS-Java.
Don't take this as anything more than an opinion, but personally I can't stand Java's GUI. It's just close enough to Windows but not quite, so it gets into an uncanny valley area where it's just really upsetting to me.
C# (and other .Net languages, I suppose) allow me to make programs that perfectly blend into Windows, and that makes me happy.
Of course, it's moot if we're not talking about developing a desktop application...
Java:
Enums in Java kick so much ass, its not even funny.
Java supports generic variance
C#:
C# is no longer limited to Windows (Mono).
The lack of the keyword internal in Java is rather disappointing.
You said:
enum types which are full-fledged classes, not just integers with a fresh coat of paint
Have you actually looked at the output? If you compile an application with enums in in then read the CIL you'll see that an enum is actually a sealed class deriving from System.Enum.
Tools such as Red-Gate (formerly Lutz Roeder's) Reflector will disassemble it as close to the orginal C# as possible so it may not be easily visible what is actually happening under the hood.
As Elizabeth Barrett Browning said: How do I love thee? Let me count the ways.
Please excuse the qualitative (vs. quantitative) aspect of this post.
Comparing these 2 languages (and their associated run-times) is very difficult. Comparisons can be at many levels and focus on many different aspects (such as GUI development mentioned in earlier posts). Preference between them is often personal and not just technical.
C# was originally based on Java (and the CLR on the JRE) but, IMHO, has, in general, gone beyond Java in its features, expressiveness and possibly utility. Being controlled by one company (vs. a committee), C# can move forward faster than Java can. The differences ebb and flow across releases with Java often playing catch up (such as the recent addition of lambdas to Java which C# has had for a long time). Neither language is a super-set of the other in all aspects as both have features (and foibles) the other lacks.
A detailed side-by-side comparison would likely take several 100s of pages. But my net is that for most modern business related programming tasks they are similar in power and utility. The most critical difference is probably in portability. Java runs on nearly all popular platforms, which C# runs mostly only on Windows-based platforms (ignoring Mono, which has not been widely successful). Java, because of its portability, arguably has a larger developer community and thus more third party library and framework support.
If you feel the need to select between them, your best criteria is your platform of interest. If all your work will run only on Windows systems, IMHO, C#/CLR, with its richer language and its ability to directly interact with Windows' native APIs, is a clear winner. If you need cross system portability then Java/JRE is a clear winner.
PS. If you need more portable jobs skills, then IMHO Java is also a winner.
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Has anyone ever written an application bigger than its .NET luggage?
People used to criticize VB6 for its 2 MB runtime but it rarely dwarfed the app it accompanied.
Today despite having Vista on my machine I had to download 35 MB of the 3.5 framework and reboot to then try out an app half that size.
When you factor in the decreased source code security I wonder why anyone would anyone develop a windows application in .NET rather than in a language that allowed for the building of native executables.
What is superior about .NET that outshadows these drawbacks when it comes to writing applications to run on Windows?
PEOPLE: Please note that this was written in February, 2009, and what is said was appropriate at that time - yelling at me in late 2012 (3+ years later) is meaningless. :-)
Delphi has some considerable advantages for Win32. Not that .NET apps are inherently bad, but try:
running a .NET app (any version) on Win95/ME, where .NET doesn't exist (AFAIK)
distributing any small ( < 1.5 MB) .NET app (yes, floppy drives still exist)
providing any .NET app on a system that has no Internet access (yes, they exist)
distributing your .NET apps in countries without widespread high bandwidth
keep people from seeing your source code without spending a ton of dough (Reflection, anyone?)
Garbage collection in .NET might be really nice, but anyone who knows anything about programming can also handle manual allocation/deallocation of memory easily with Delphi, and GC is available with reference-counted interfaces. Isn't one of the things that brought all of the non-programmers to proliferation the pseudo-GC of VB? IMO, GC is one of the things that makes .NET dangerous, in the same way VB was dangerous - it makes things too easy and allows people who really have no clue what they're doing to write software that ends up making a mess. (And, before I get flamed to death here, it's great for the people who do know what they're doing as well, and so was VB; I'm just not so sure that the advantage to the skilled outweights the hazards to us from the unskilled. )
Delphi Prism (AKA Rem Objects Oxygene, formerly Chrome) provides the GC version of Delphi that those who need it are looking for, along with ASP.NET and WPF/Silverlight/CE, with the readability (and lack of curly braces) of Delphi. For those (like me) for which Unicode support isn't a major factor, Delphi 2007 provides ASP.NET and VCL.NET, as well as native Win32 support. And, at a place like where I work, when workstations are only upgraded (at a minimum) every three years, and where we just got rid of the last Win95 machine because it wasn't a priority to upgrade, the .NET framework is an issue. (Especially with company proxy requirements only allowing Internet access to a handful of people, limiting bandwidth and download capabilities, and proper non-admin accounts with no USB devices allowed, all still running across a Netware network - no such thing as Windows Update, and never a virus so far because nothing gets in.)
I work some in .NET languages (C#, Delphi Prism), but the bread and butter both full-time and on the side, comes from Win32 and Delphi.
Okay, I doubt this will persuade you as you don't want to be persuaded, but here's my view of the advantages of .NET over older technologies. I'm not going to claim that every advantage applies to every language you mentioned in the question, or that .NET is perfect, but:
A managed environment catches common errors earlier and gives new opportunities:
Strong typing avoids treating one type as another improperly
Garbage collection largely removes memory management concerns (not totally, I'll readily admit)
"Segmentation fault" usually translates to "NullReferenceException" - but in a much easier to debug manner!
No chance of buffer overruns (aside from the potential for CLR bugs, of course) - that immediately removes a big security concern
A declarative security model and a well-designed runtime allows code to be run under a variety of trust levels
JITting allows the CLR to take advantage of running on a 64 bit machine with no recompilation necessary (other than for some interop situations)
Future processor developments can also be targeted by the JITter, giving improvements with no work on the part of the developer (including no need to rebuild or distribute multiple versions).
Reflection allows for all kinds of things which are either impossible or hard in unmanaged environments
A modern object-oriented framework:
Generics with execution time knowledge (as opposed to type erasure in Java)
Reasonable threading support, with a new set of primitives (Parallel Extensions) coming in .NET 4.0
Internationalisation and Unicode support from the very start - just one string type to consider, for one thing :)
Windows Presentation Framework provides a modern GUI framework, allowing for declarative design, good layout and animation support etc
Good support for interoperating with native libraries (P/Invoke is so much nicer than JNI, for example)
Exceptions are much more informative (and easier to deal with) than error codes
LINQ (in .NET 3.5) provides a lovely way of working with data in-process, as well giving various options for working with databases, web services, LDAP etc.
Delegates allow a somewhat-functional style of coding from VB and C#; this is better in C# 3.0 and VB9 due to lambda expressions.
LINQ to XML is the nicest XML library I've used
Using Silverlight as an RIA framework allows you to share a lot of code between your lightweight client and other access methods
A mostly-good versioning story, including binding redirection, runtime preference etc
One framework targeted by multiple languages:
Simpler to share components than with (say) COM
Language choice can be driven by task and team experience. This will be particularly significant as of .NET 4.0: where a functional language is more appropriate, use F#; where a dynamic language is more appropriate, use IronRuby or IronPython; interoperate easily between all languages
Frankly, I just think C# is a much cleaner language than VB or C++. (I don't know Delphi and I've heard good things about it though - and hey, you can target .NET with Delphi now anyway.)
The upshot of most of this - and the soundbite, I guess - is that .NET allows faster development of more robust applications.
To address the two specific issues you mentioned in the question:
If your customer is running Vista, they already have .NET 3.0. If they're running XP SP2 or SP3, they probably have at least .NET 2.0. Yes, you have to download a newer version of the framework if you want to use it, but I view that as a pretty small issue. I don't think it makes any sense to compare the size of your application with the size of the framework. Do you compare the size of your application with the size of the operating system, or the size of your IDE?
I don't view decompilation as nearly such a problem as most people. You really need to think about what you're afraid of:
If you're afraid of people copying your actual code, it's usually a lot easier to code from scratch if you're aware of the basic design. Bear in mind that a decompiler won't give local variable names (assuming you don't distribute your PDB) or comments. If your original source code is only as easy to understand as the decompiled version, you have bigger problems than piracy.
If you're afraid of people bypassing your licensing and pirating your code, you should bear in mind how much effort has gone into stopping people from pirating native applications - and how ineffective it's been.
A lot of the use of .NET is on the server or for internal applications - in neither of these cases is decompilation an issue.
I've written more on this topic in this article about decompilation and obfuscation.
To name a few:
Automatic memory management, garbage collection
Type safety
Bounds checking
Access to thousands of classes that you will not have to create
OK first up, No one language/platform is ever going to be universally superior.
Specialization will always provide a better use case in certain areas but general purpose languages will be applicable to more domains.
Multi-paradigm languages will suffer from complex boundary cases between paradigms e.g.
Type inference in any functional language that also allows OOP when presented with sub classes
The grammar of C++ is astonishingly complex, This has a direct effect on the abilities of its tool chain.
The complexities of co/contra variance coupled with generics in c# is very hard to understand.
Older languages will have existing code bases that work, this is both positive (experience, well tested, extensive supporting literature) but also a negative (the resulting inertia against change, multiple different ways to do things leading to confusion for new entrants).
The selection/use of both languages and platforms is, as are most things, a balancing of the pros and cons.
In the following lists Delphi has some of the same pros and cons, but differs on many too.
Potential Negatives of .Net (if they are not an issue to you they aren't negatives)
Yes, you need the runtime deployed (and installed), and it's big.
If you wanted a language with multiple inheritance you're not going to get it
The BCL collections library has some serious flaws
Not widely supported outside the MS universe (mono is great but it lags the official implementation significantly)
Potential patent/copyright encumbrance
Jitted (ignoring ngen) start up time is always going to be slower and more memory will be needed.
There are more but these are the highlights.
Potential Positives (again if they don't matter to you)
A universal GC, no reference counting that prevents certain data structures being usable, I know of no widely used Functional language without GC, I can't think of significant language of the last 10 years without at least optional GC. If you believe this is not a big deal you would appear to be in a minority.
A large BCL (some parts not so good as others but it's very broad)
Vast numbers of languages (and a surprising number of paradigms) can be used and interact with each other (I use c#, f#, C++/CLI within one wider application using each where it makes most sense but able to easily use aspects of one from another).
Full featured introspection combined with declarative programming support. A wide variety of frameworks become much simpler and easy to use in this manner.
Jitted - alterations in underlying CPU architecture can be largely transparent, sophisticated runtime optimizations not available to pre-compiled languages are possible (java is doing rather better on this currently)
memory access safety
Fusion dll loading and the GAC for system dlls
Likewise specifically for c#
Con:
Syntax based on C underpinnings
(pre 4.0) late binding solely via inheritance
More verbose than some imperative languages
poor handling of complex embedded literals (regexes/xml/multi line strings)
variable capture within closures can be confusing
nested generators are both cumbersome and perform appallingly
Pro:
Syntax based on C underpinnings
Much functional support through lambdas
Expressions allowing compile time validation of non code areas such as Linq to SQL
Strongly typed but with some Type inference to make this easier
if you really need to unsafe is there for you
interaction with existing C++ ABI code via P/Invoke is both simple and clear.
multicast event model built in.
light weight runtime code generation
The C underpinnings really is a pro and con. It is understandable by a vast number of programmers (compared to pascal based style) but has a certain amount of cruft (switch statements being a clear example).
Strong/Weak/Static/Dynamic type systems are a polarising debate but it is certainly not contentious to say that, where the type system is more constraining it should strive to not require excessive verbosity as a result, c# is certainly better than many in that regard.
For many internal Line of Business applications a vast number of the .Net platform Cons are absolutely immaterial (controlled deployment being a common and well solved problem within corporations).
As such using .Net (and this does largely mean c#, sorry VB.Net guys) is a pretty obvious choice for new development within a windows architecture.
The "simplicity" of developing complex(and simple) applications using it. A lot of basic stuff is already coded for you in the framework and you can just use it. And downloading 35mb file today is much easier than 2mb file 8-6 years ago.
There are a lot of reasons. I don't know much about RealBasic, but as far as Delphi goes:
Less widespread than .NET, smaller development community. Many of the Delphi resources on the net are ancient and outdated.
Until Delphi 2009, Delphi didn't have full unicode support.
I don't know about Delphi 2009, but 2007 didn't have very good garbage collection. It had some sort of clunky reference counting that required some intervention on behalf of the developer. .NET has a much more advanced GC that does virtually everything for you.
.NET has a larger standard library and more up-to-date 3rd party libraries.
.NET languages like C# are arguably better, and certainly easier to understand for those new to the language.
There's a lot of supposed advantages cited by .NET developers here that shouldn't be in that comparison, simply because Delphi has them as well:
Type safety
Bounds checking
Access to thousands of classes (components) that you will not have to create
There are however some things in .NET that Delphi doesn't have out-of-the box, and only some of those can be added by libraries and own code. To name a few:
Support for multiple languages working on top of the same runtime - allowing to choose the matching language for the problem (e.g. functional programming using F#)
Dynamic source code generation and compilation - this is something so alien to Delphi programmers that they probably don't even see how it could be useful [1]
Multicast events
Better multi-threading support (for example BackgroundWorker class, asynchronous delegates)
Seamless support for both 32 and 64 bit processes
Weak references
[1] If you don't know but are interested, check out the home page of Marc Clifton, especially the articles about declarative programming.
Edit: I'd like to respond to the comment by Mason Wheeler:
Re dynamic code: I know that there are solutions to have Pascal scripting embedded in the application. There is however a distinct difference between making parts of your internal object hierarchy available to the scripting engine, and having the same compiler that is used for your code available at runtime as well. There are always differences between the Delphi compiler and the compiler of the scripting engine. Anyway, what you get with .NET goes far beyond anything that is available for Delphi. And anyway, it's not the point whether one would be able to code similar infrastructure for Delphi, the point is that with .NET it's already there for you, when you need it.
Re Multicast events: Exactly, there's ways to code it, but it's not part of Delphi / the VCL out-of-the-box. That's what I was saying above.
Re weak references: You are sadly mistaken. Try to use interfaces in a non-trivial way, creating circular references on the way. Then you have to start to use typecasts and wish for weak references.
Well, the .NET Framework is shared for all .NET applications, so you have it only once on your machine and 35MB are nothing today (compare it to the size of your Vista installation). For your second .NET application you don't have to download it again.
For Windows app, .NET (using C# or whatever) gives you more direct access to the latest and greatest Windows features. It's also very well supported by Microsoft, has a huge community and lots of books written about it.
REALbasic (now Xojo) is for cross-platform apps. Using it just on Windows can sometimes be useful, but that would not be its strength (which is that it's amazingly easy to use).
I don't know much about Delphi.
From what I can see RealBASIC doesn't have much (if anything) in the way of Object Relational tools and probably wouldn't be as good a choice for n-tier, database-centric applications.