is it possible edit kdbx from dot net application?
Does it exist anywork around how to do it?
Thank you for tips
You can use KeePassLib.dll from the source code package or just include the KeePass source code in your application. (Source code links are at the bottom of the KeePass downloads page.)
The KeePass database is an encrypted XML file. Once you have decrypted it you can edit it with any editor.
Decrypting and editing is performed by KeePass (obviously) and a number of other compatible applications - see the downloads page of the web site. There is no requirement for an application to be written in dot net, but it must be written to open and manipulate a KeePass database.