We Keep Coding

Auto Patcher for game (Efficient Auto Updater)

I want an auto updater that detect modified game files (by comparing files on the client-side and a server) and only download modified files.
The scenario is that there's about one thousand clients in a network, that use same application. If a new version of the application is available, they all have to get the new version.
I see a www.aldera.to game if you install the files their Aelra_patcher application auto patch the files from the server side. It do the exact thing I want:Getting the newest files from server when the patcher is run. But the problem is that clients wrote in C#, and I can't use IcePatch2 inside my application.
So far, the best solution I found is to get .NET Application Updater Component and customize it to fit my needs. But I prefer a solution that dose not require me to maintain another application.
Any idea?

Managing file locks is fairly simple. The process should go something like this:
The game application downloads the installer, if there is any
The game application runs the installer and exits
The installer starts doing the work of updating files as needed. If any files are locked it may wait a short while and try again, or ask the user if it is ok to close the application that have locked the files.
But the topic of minimizing update time and bandwith is a fairly complex. You might want to read Raymon Chens articles on Windows Update Formats to get some appreciation for the various issues.
I'm not familiar with IcePatch2, but it seems to be a fairly generic file synchronization tool. This may be appropriate for your specific use case, but I would expect some use cases to benefit from a more specialized approach. You could for example use knowledge of things like file or resource versions to avoid much of the work a more generic tool has to do.

c# create media at runtime

I want to add a backup functionality to my app in the sense that the app will allow users to create a self-contained environment (data + executable + autorun.inf file) on an external device (CD, CD-ROM or USB key) so that users can retrieve (in read only mode) their stored environment at a given point in time.
I've read here about making an auto-bootable USB (which I suspect will be the same for a CD or DVD).
edit I meant "auto-executing", not "auto-bootable"!
I know about IMAPI or other approaches that are now several years old. Is there any alternative/standard approach to create media this way? I'd like a generic way to create either CD/DVD or USB devices (non-bootable).

You need to make sure to not confuse Booting and Windows Autorun.
auto-bootable USB
refers to an external USB drive from which you can boot your computer.
I doubt that's what you are looking for, given the linked Stackexchange question. The information you already found is actually what you are looking for, and the advice given there seems pretty accurate.
What you need to do is:
Create the media with your data. In case of USB sticks this is as easy as copying the data to the stick. Optical media (CD/DVD) need to be burned, and that can only be done using the Windows API, which has already be discussed here.
If you want to use the Windows autorun feature (which I would ignore*), you'll need to create a file called Autorun.ini in the root directory of your media. You already have found the required content of that file here.
* Why I would skip the autorun feature.
First of all, there's no real alternative to the Windows autorun feature.
It was controversial, at best, in earlier versions of Windows. Since USB sticks went mainstream, autorun became nothing more than an automatic virus installation feature. Soon after everyone started disabling it. Because of this recent versions of Windows seem to have dropped it or disable it by default.
An exception to this would be the Icon=diskicon.ico option, which allows you to change the icon of the drive. This might be still working, even if autorun is disabled.

C# - Locking folders from being edited

i'm making a small project. it's Windows Form Application. i got some sources in a folder (C:/sources). When my program runs, it uses sources from the folder. Currently i can edit the folder by windows explorer, it can cause errors for my program. So i want to lock the folder (C:/sources) from being edited/renamed/deleted when my program runs. How to do so?
EDIT;
Is it possible to show a message like this when user has tried to edit the folder:
"the action cannot be completed because the folder or a file in it is open in another program"
the program that we are talking about is mine..

There are a couple of approaches that you could venture and they vary in difficulty of implementation. It all depends on how important this task is for you. But, before discussing these options; can't you embed those resources in your WinForms application instead? If this is not an option then you can do one of the following:
Write a device driver that can prohibit the access of such resources if your application is running. There are fallbacks to this approach. For example one can impersonate your application by having the same name. But, am not getting in to too much details in trying to break any approach as I am trying to address possible solutions to the current problem. There are different types of drivers that you can consider. Probably the simplest form of this approach would be to implement a mini-filter driver.
Hook certain API's like CreateFile(), NtCreateFile(), ZwCreateFile() although there are many ways to circumvent such mechanism of defense. But, again we are only venturing what you can do to address this constraint of yours.
Open these resources directly from your application and lock it exclusively. For example:
File.Open("test.txt", FileMode.Open, FileAccess.Read, FileShare.None);
as this will result in people getting the message that you desire if they try to open the file.
Maybe you can give more information on what these resources are and we can help you determine which is the best way to protect your files in a reasonable fashion?

Although I don't believe it's the best idea to have files that are critical to the application in a open area like the C: drive, I would look into NTFS file permissions and set the folder to read only, but this wont stop administrative users
See these two posts
restrict access to folder outside of program c#
Setting NTFS permissions in C#.NET

visual c# button opens file without specifying drive

I work for an IT company where we all carry around flash drives that have our most used programs on them.In my spare time I am hoping to create a "main menu" item that is kind of a fun and convenient way to access these files. I am working on creating this using Visual Studio 2013 and using visual C# windows forms. I have come across a snag however that I can't seem to find a workaround for. I am by no means fluent in C#, but I need to have a button on the windows form open a file without specifying what drive it comes from. I understand that I have to specify a path, but as these will be stored on the flash drives of myself and my coworkers I cannot foresee that the path will always begin with E:. Depending on what USB slot the drive is plugged into it could be N: or F: or the like. I have provided an example below:
Using what I currently know I am opening files using this line of code:
System.Diagnostics.Process.Start("C:/Users/Myname/Desktop/Asmodeus/Anti-Virus/Anti-Virus Installers/avast_free_antivirus_setup.exe");
Is there any way possible I can have the file open simply from
System.Diagnostics.Process.Start("Asmodeus/Anti-Virus/Anti-Virus Installers/avast_free_antivirus_setup.exe");
or something of that nature?
Thanks in advance.
There must have been some mis-communication when I asked my question previously. what I am looking to do is open an executable file via a button click on the windows form using a relative path. I am not able to specify the absolute path because the application will be run from a flash drive and therefore will change depending on what USB slot it is currently inserted into.
What I am hoping to accomplish is insert a line of code that will allow me to open an executable file that is located in the \bin\debug folder along with the application itself. I have a picture for clarification but apparently do not have enough reputation to post it. Thank you and sorry for the earlier confusion.

Usually you can just use Environment.GetFolderPath (MSDN) to give you what you need. It doesn't do absolutely everything, but if you need Desktop and the like, that is plenty.
Depending on the target version of .Net, the SpecialFolders exposed are not all there. It may turn out that you need more than they provide, but in your case it doesn't sound like it.
If there is more you need that is not covered in the default, check out this project. I'm sure there are others like it, but it does a little more than the default BCL version, using the API directly. It is at least something to read and learn (and translate from vb.. use an online translator, very quick). I haven't looked at it, but it seems like you are learning this c#/.net thingy, so it might be helpful
This article is about accessing Windows special folders.
These folders include your “Favorites”, “Cookies”, system libraries and the like.
Here is code, including a large number of constant definitions, plus documentation,
allowing access to and creation of these folders.

C# How to to tell what process is using a file?

I am getting a pretty common, "The process cannot access the file because it is being used by another process."
Now I am nearly certain that the only process accessing this file is from code that I have written and I've been careful to use a using statement around accessing it.
But to be 100% sure, is there anyway to check this programatically when this error occurs?

There is also a small tool handle.exe in Sysinternals Suite that does exactly what you need. Use it from the command line:
handle.exe -a <filename>
Of course under Vista and Windows 7 this tool must be run elevated.

e.g. oh.exe from the Resource Kit and Process Explorer from sysInternals both show who is using what
Both of them use techniques not available in C#.

Windows Vista adds a new function, GetRunningObjectTable which you can use to detect which program has a file open. This only works in Vista+, and it only works when the application that has the file open actually implements supports for IFileIsInUse (e.g. Office supports it, but most 3rd-party apps probably don't).
Other than that, the usual way this is implemented is by opening each process, enumerating the file handles they have open and searching for the filename in question. This is pretty low-level, and would require quite a bit of P/Invoke to implement in C#, but it's not impossible.
It's usually easy enough just to open up Process Explorer and let it do the search.