A Universal Database connection program

I never use a DNS connection, I think that is very inconvenient, the following part of the program can be said to be a universal database connection program can almost connect all the MS database, you take to study it (this program is "ASP Web page Production tutorial" In this book-a good book):
<%
'---------------------------------------------------
Function getmdbconnection (FileName)
Dim Provider, DBPath Provider = "provider=microsoft.jet.oledb.4.0;"
DBPath = "Data source=" & Server.MapPath (FileName)
Set getmdbconnection = getconnection (Provider & DBPath)
End Function '---------------------------------------------------
Function getsecuredmdbconnection (FileName, Password)
Dim Provider, DBPath Provider = "provider=microsoft.jet.oledb.4.0;"
DBPath = "Data source=" & Server.MapPath (FileName)
Set getsecuredmdbconnection = getconnection (Provider & DBPath &); Jet oledb:database password= "& Password)
End Function '---------------------------------------------------
Function getdbcconnection (FileName)
Dim Driver, sourcetype, DBPath Driver = "Driver={microsoft Visual FoxPro Driver};"
SourceType = "SOURCETYPE=DBC;"
DBPath = "sourcedb=" & Server.MapPath (FileName)
Set getdbcconnection = getconnection (Driver & sourcetype & DBPath)
End Function '---------------------------------------------------
Function getdbfconnection (Directory)
Dim Driver, sourcetype, DBPath Driver = "Driver={microsoft Visual FoxPro Driver};"
SourceType = "SOURCETYPE=DBF;"
DBPath = "sourcedb=" & Server.MapPath (Directory)
Set getdbfconnection = getconnection (Driver & sourcetype & DBPath)
End Function '---------------------------------------------------
Function getexcelconnection (FileName)
Dim Driver, DBPath Driver = "Driver={microsoft Excel Driver (*.xls)};"
DBPath = "dbq=" & Server.MapPath (FileName)