Class Libraries & REST APIs for the developers to manipulate & process Files from Word, Excel, PowerPoint, Visio, PDF, CAD & several other categories in Web, Desktop or Mobile apps. Develop & deploy on Windows, Linux, MacOS & Android platforms....//Select a range of cells Excel . Range range = ( Excel . Range ) excelWorksheet...excelWorksheet . get_Range ( "A1:B4" , Type . Missing ); //Add...