A universal class to complete import data from an Excel file into a database

How can I do that?
Two File
One is update data to database

First step
I will define two sesion to write the operating table and operating columns in server.
Two Step
Tell the customer where and how many columns they can update.

Column name 1: Real column name 1 # column name 1: Real column name 1 # column name 1: Real column name 1

// Get the data from excle
String strconn = "provider = Microsoft. Jet. oledb.4.0; Data Source = D :\\ withdrawal table. xls; extended properties = \" Excel 8.0 ;\"";
Oledbconnection conn = new oledbconnection (strconn );
Conn. open ();
Oledbdataadapter da = new oledbdataadapter ("select * from [sheet1 $]", Conn );
Dataset DS = new dataset ();
// Import data to a dataset
Da. Fill (DS, "tablename");

// Define SQL dataadapter
Define a dataadapter
Sqldataadapter adapter = new sqldataadapter ();
Adapter. selectcommand = new sqlcommand (query, Conn );
Adapter. Update (DS, "tablename")

Another is import data to database