xlstool

let xls read/write easy.

DEMO

var xls = new Excel2003File();
var sheet = xls.ToSheet("TEST");
var a = sheet.ToRow(1);
a.ToCell("A").SetValue("AS");
a.Next();
a.ToCell("A").SetValue("test");
var style = a.ToCell("A").NewStyle();
style.Font.FontHeightInPoints = 32;
style.SetBold();
style.Style.WrapText = true;
a.Height = 32;

using (var f2 = File.Create("a.xls")) xls.ToStream(f2);