I have run the Passing Authentication example
and want to do it myself,i have created a BizComponent to read the username and password from flat file,it's ok;
but when i try to create the BizDriver to connect to the database,how can i set the username and password with those i get from the flat file,i set the username="%username%",password="%password%",it show me the error of invalidate username and password,i know i have't get the value from the flat file,what can i do next?

Thanks in advance!