Questions from someone wanting to start C#
Hi,
I have been fairly active on the VB6 forum trying to learn. Anyways things have changed and the project I am working on is being under consideration to change from VB6 to C#.NET
I am an entry level programmer not too much experience, with most experience with web development in java and PHP, not application development.
Ok so I have VS.NET 2003.
So onto the questions
1. I see a lot of discussion about Managed vs Unmanaged(native?) code. What does this exactly mean, maybe as article link or somewhere I can read up on this would help.
2. Where is a good place to start learning how to program in C#? Books or web resources? I realize its a lot like Java and C++ which should be ok for me to start with as I am familiar with both.
3. I had a hard time with VB6 as I found it impossibe to navigate through the Help files. Never finding what I needed.
I guess im just used to java's API being so simple. Typing in the class shows me all its methods etc. Was I doing something wrong? How can I get the information I need from the help files?
Any more advise from advanced programmers would be helpful.
Thanks a ton
Re: Questions from someone wanting to start C#
Ok found this about my Q1. I understand it more now but still a little confused by this all. Mainly what the big deal is about?
Quote:
What Is Managed Code?
Managed Code is what Visual Basic .NET and C# compilers create. It compiles to Intermediate Language (IL), not to machine code that could run directly on your computer. The IL is kept in a file called an assembly, along with metadata that describes the classes, methods, and attributes (such as security requirements) of the code you've created. This assembly is the one-stop-shopping unit of deployment in the .NET world. You copy it to another server to deploy the assembly there—and often that copying is the only step required in the deployment.
Managed code runs in the Common Language Runtime. The runtime offers a wide variety of services to your running code. In the usual course of events, it first loads and verifies the assembly to make sure the IL is okay. Then, just in time, as methods are called, the runtime arranges for them to be compiled to machine code suitable for the machine the assembly is running on, and caches this machine code to be used the next time the method is called. (This is called Just In Time, or JIT compiling, or often just Jitting.)
As the assembly runs, the runtime continues to provide services such as security, memory management, threading, and the like. The application is managed by the runtime.
Visual Basic .NET and C# can produce only managed code. If you're working with those applications, you are making managed code. Visual C++ .NET can produce managed code if you like: When you create a project, select one of the application types whose name starts with .Managed., such as .Managed C++ application..
What Is Unmanaged Code?
Unmanaged code is what you use to make before Visual Studio .NET 2002 was released. Visual Basic 6, Visual C++ 6, heck, even that 15-year old C compiler you may still have kicking around on your hard drive all produced unmanaged code. It compiled directly to machine code that ran on the machine where you compiled it—and on other machines as long as they had the same chip, or nearly the same. It didn't get services such as security or memory management from an invisible runtime; it got them from the operating system. And importantly, it got them from the operating system explicitly, by asking for them, usually by calling an API provided in the Windows SDK. More recent unmanaged applications got operating system services through COM calls.
Unlike the other Microsoft languages in Visual Studio, Visual C++ can create unmanaged applications. When you create a project and select an application type whose name starts with MFC, ATL, or Win32, you're creating an unmanaged application.
This can lead to some confusion: When you create a .Managed C++ application., the build product is an assembly of IL with an .exe extension. When you create an MFC application, the build product is a Windows executable file of native code, also with an .exe extension. The internal layout of the two files is utterly different. You can use the Intermediate Language Disassembler, ildasm, to look inside an assembly and see the metadata and IL. Try pointing ildasm at an unmanaged exe and you'll be told it has no valid CLR (Common Language Runtime) header and can't be disassembled—Same extension, completely different files.
Re: Questions from someone wanting to start C#
Managed Code is code that is created with the .NET framework
Re: Questions from someone wanting to start C#
Quote:
Originally Posted by Ctwizzy
1. I see a lot of discussion about Managed vs Unmanaged(native?) code. What does this exactly mean, maybe as article link or somewhere I can read up on this would help.
C# & vb.net creates managed code.
Quote:
2. Where is a good place to start learning how to program in C#? Books or web resources? I realize its a lot like Java and C++ which should be ok for me to start with as I am familiar with both.
MSDN.com
Visual C#.net from microsoft press is a good beginners book
Quote:
3. I had a hard time with VB6 as I found it impossibe to navigate through the Help files. Never finding what I needed.
I guess im just used to java's API being so simple. Typing in the class shows me all its methods etc. Was I doing something wrong? How can I get the information I need from the help files?
1: Create an new project/solution
2:In the video studio.net IDE select the view menu. Select Object Browser. That will show you the .net framework that is already available to your project. That is a good start.
3: Select the member you want to know about and hit F1. If a help file exists it will display it.
