i need to update my table column votecount when a user voted but im having this error and i dont know what to do with it.
private void Vote(string VoteId)
You need to change your parameter @Prsdent
to :Prsdent
See: OracleCommand.Parameters Property
When using named parameters in an SQL statement called by an OracleCommand of CommandType.Text, you must precede the parameter name with a colon (:).
Also consider enclosing your command and connection object in using statement as that will ensure proper disposal of resources.