How to execute a custom file with C#?

Question

I'm writing a application by C# in application i creat a file with extension is .wws and i want when user double click on this file then my program can realize and execute to read it. Somebody can help me?.

Long Thanh · Answer

I using Visual studio 2005 too and i can creat setup project as in VS 2003 Do you check carefully?

Antti · Answer

No problem;) Well there actually is. I encountered a problem myself with this same issue: I use Visual C# Express 2005 and it has no such thing as Installation Project! I don't know how to do the extension associations with Visual C# Express 2005 someone have any knowledge about that? Do I have to use some 3rd party installation program (any free & good will do)?

Long Thanh · Answer

Thank you very much i think my problem is ok (^_^).

Antti · Answer

>>Well you can't do it you have to write another program that opens your wws file.The operating system didn't recognize it and can't execute it directly! That doesen't really make sense to me of course C# app must be able to register a file type to it. In installation phase you must somehow associate the filetype with your program. If C# doesen't have method to associate the filetype with program you must find some WinAPI function to do it. Assosiationg the filetype has nothing to do with the programming language it is Windows's feature. >>write another program that opens your wws file How the other program changes the situation? It have to register the filetype anyway. Edit: A solution I quickly searched google and found one possible answer. I have no time to try it but you take it a try: http://www.vbcity.com/forums/topic.asp?tid=72258 . So basically best way to register a filetype seems to be the use of an installation project created with visual studio. When you install the program your files can be associated. When you uninstall the program the file association is also uninstalled. If you get that working let us know. The other way to associate the filetype is to modify registry values directly but if installer does it for you it is better choice. But i presume you must have somekind of an interface in your program to open the file that way. My guess is that your program will just open if you don't make any modifications to it. It would be logical that windows passes the filenames to Main method of the program so you can open the file in program. static void Main( string [] args) { if (args.Length > 0 ) { //open the file(s) here remember to use all necessary sanity checks and try-catches foreach ( string filename in args) { //open each file } } else { //start program normally } } >>How make os can realize this file like when you double click on *.txt file then Notepad will be invoke to read file with extension is .txt OS keeps file associations in registry so that way OS can tell what program to call. You can modify these associations by hand in Windows Explorer Tools->Folder Options...->File Types->Advanced.

Long Thanh · Answer

Could you show me another way if don't use C#? How make os can realize this file like when you double click on *.txt file then Notepad will be invoke to read file with extension is .txt

Tom Diann · Answer

Well you can't do it you have to write another program that opens your wws file.The operating system didn't recognize it and can't execute it directly!