How to get the Cell value of A1(Cell Address) using npoi frame work in C#

I have Excel Cell Address like A1,A2. So, how to access this cell programmatically using "NPOI" framework in C#. How to implement cell reference function in C#.

CellReference cr = new CellReference("A1"); row = mySheet.getRow(cr.getRow()); cell = row.getCell(cr.getCol());

I found this code written in java,Im using Npoi Framework