i have a folder.geodatabase contain a lot of files with different extensions is there any way to make it one geodatabase file to use it programmatically with C# code in my .Net application
No a file geodatabase is a folder of several files as you see. There is no way to make it one file unless you zip the FGDB and then unzip it on the client. You may also want to look into the FGDB API:
File Geodatabase API version 1.5.1 available!
ok thank you .... but may be you can help me with my issue .. i want to load street map as feature layer in my .Net application
Sorry I don't have an answer for that. You may want to post this question in the ArcObjects SDK space
Retrieving data ...