How to focus or select a cell in Excel

Question

How to focus a cell in Excel VSTO using C# or to select first cell using C# in VSTO?

Answer 1

Here is one way:

Excel.Worksheet activeSheet = ThisAddIn.ExcelApplication.ActiveSheet;
var range = activeSheet.get_Range("A1", "A1");
range.Select();

ThisAddIn is the name of my test project.

Answer 2

To select the A2 cell, for example:

Excel.Worksheet Worksheet = excel.ActiveWorkbook.ActiveSheet;
Worksheet.get_Range([1,2], System.Reflection.Missing.Value).Select();