Please open an excel application go to file menu then new. There will be the
action pane with the blank workbook and from existing workbook. then click
blank workbook. Then a new excel instance window will pop up. How can I do
the same behavior using C# language?

thank you

Hi

We can automation Excel.
The code line below will create two new workbooks.

Excel.Application exApp = new Excel.ApplicationClass();
exApp.Visible = true;
exApp.Workbooks.Add(Missing.Value);
exApp.Workbooks.Add(Missing.Value);

Here is a KB article about how to automation Excel in C# for your reference.
302084 How To Automate Microsoft Excel from Microsoft Visual C# .NET
http://support.microsoft.com/?id=302084

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.