Excelからの読み込み、書き出し　http://jp.rubyist.net/magazine/?0004-Win32OLE

gistfile1.rb

#! ruby -Ks
# -*- coding: sjis -*-

require 'win32ole'
 
 module Worksheet
   def [] y,x
     cell = self.Cells.Item(y,x)
     if cell.MergeCells
       cell.MergeArea.Item(1,1).Value
     else
       cell.Value
     end
   end
 
   def []= y,x,value
     cell = self.Cells.Item(y,x)
     if cell.MergeCells
       cell.MergeArea.Item(1,1).Value = value
     else
       cell.Value = value
     end
   end
 end
 
 def getAbsolutePath filename
   fso = WIN32OLE.new('Scripting.FileSystemObject')
   return fso.GetAbsolutePathName(filename)
 end
 
 def openExcelWorkbook filename
   filename = getAbsolutePath(filename)
 
   xl = WIN32OLE.new('Excel.Application')
   xl.Visible = true
   book = xl.Workbooks.Open(filename)
   begin
     yield book
   ensure
     xl.Workbooks.Close
     xl.Quit
   end
 end
 
 
app = WIN32OLE.new('Excel.Application')
book = app.Workbooks.Open("C:\\work\\ruby\\test.xls")
#使っているワークシート範囲を一行ずつ取り出す
for row in book.ActiveSheet.UsedRange.Rows do
  #取り出した行から、セルを一つづつ取り出す
  for cell in row.Columns do
    p cell.Address
    p cell.Value
    p '-------'
  end
end

book.close(false)
app.quit

#Excelに書き出し
openExcelWorkbook("test.xls") do |book|
   sheet = book.Worksheets.Item(1)
   sheet.extend Worksheet
 
   sheet[1,4] = "English"
   sheet[2,4] = 5
   book.Save
end