How does one import data into Excel by dataset?

/** // <Summary>
/// Import all data in dataset to excel
/// You need to add COM: Microsoft Excel Object Library
/// Using Excel;
/// </Summary>
/// <Param name = "filepath"> file path </param>
/// <Param name = "ds"> dataset to be stored </param>
Public static void exporttoexcel (string filepath, dataset DS)
...{
Object omissing = system. reflection. Missing. value;
Excel. applicationclass xlapp = new excel. applicationclass ();
Try
...{
// Open an Excel file. The following are Office 2000.
Excel. Workbook xlworkbook =
Xlapp. workbooks. Open (filepath, omissing, omissing,
Omissing,
Omissing,
Omissing,
Omissing );
 
Excel. worksheet xlworksheet;
// Loop all datatable
For (INT I = 0; I <Ds. Tables. Count; I ++)
...{
// Add a new sheet
Xlworksheet = (Excel. worksheet) xlworkbook. worksheets. Add (omissing, omissing, 1, omissing );
 
// Use tablename as the newly added Sheet Name
Xlworksheet. Name = Ds. Tables [I]. tablename;
 
// Retrieve all values in this able and store them in stringbuffer
System. Text. stringbuilder stringbuffer = new system. Text. stringbuilder ();
 
For (Int J = 0; j <Ds. Tables [I]. Rows. Count; j ++)
...{
For (int K = 0; k <Ds. Tables [I]. Columns. Count; k ++)
... {Stringbuffer. append (string) ds. Tables [I]. Rows [J] [k]);
If (k <Ds. Tables [I]. Columns. Count-1)
Stringbuffer. append ("/t ");
}
Stringbuffer. append ("/N ");
}
// Use the system clipboard
System. Windows. Forms. clipboard. setdataobject ("");
 
// Put stringbuffer into the clipboard
System. Windows. Forms. clipboard. setdataobject (stringbuffer );
 
// Select the first cell in the sheet page (subscript starts from 1)
(Excel. Range) xlworksheet. cells [1, 1]). Select ();
 
// Paste the content in the clipboard in sheet
Xlworksheet. paste (omissing, omissing );
 
// Clear the system clipboard
System. Windows. Forms. clipboard. setdataobject ("");
}
 
// Save and close this workbook
Xlworkbook. Close (Excel. xlsaveaction. xlsavechanges, omissing, omissing );
System. runtime. interopservices. Marshal. releasecomobject (xlworkbook );
Xlworkbook = NULL;
}
Catch (exception ex)
...{
MessageBox. Show (ex. Message );
}
Finally
...{
// Release the COM Object
Xlapp. Quit ();
System. runtime. interopservices. Marshal. releasecomobject (xlapp );
GC. Collect ();
}
}