Question

I want to insert datas an existing Excel (.xls) file with Ruby under Linux. This file has already data, it has some format properties and it contains macros.

I tried to insert data into the file with the spreadsheet gem but when I save modifications, the format and all the macros of the file are lost.

Here’s an example of a simple modification where I meet this problem :

book = Spreadsheet.open('myOriginalFile.xls')
sheet = book.worksheet 0
sheet.write('C12','hello')
book.write('myModifiedFile.xls')

I tried lots of things, did research on forums and the web but I didn’t find a solution…
Does anyone has an idea?

Answer 1

I found a solution :

I use the POI library of Apache which is written in java with the rjb gem (Ruby Java Bridge, which allows to use java libraries with ruby). POI allows to keep macros and formulas of existing xls file and to modify it.

For those who need, here’s how to set up rjb to use POI :

    # JVM loading
    apache_poi_path = File.dirname(__FILE__)+'/poi-3.8/poi-3.8-20120326.jar'
    Rjb::load("#{apache_poi_path}", ['-Xmx512M'])

    # Java classes import 
    @file_class = Rjb::import('java.io.FileOutputStream')
    @workbook_class = Rjb::import('org.apache.poi.hssf.usermodel.HSSFWorkbook')
    @poifs_class = Rjb::import('org.apache.poi.poifs.filesystem.POIFSFileSystem')
    Rjb::import('org.apache.poi.hssf.usermodel.HSSFCreationHelper')
    Rjb::import('org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator')
    @cell_reference_class = Rjb::import('org.apache.poi.hssf.util.CellReference')
    @cell_class = Rjb::import('org.apache.poi.hssf.usermodel.HSSFCell')
    # You can import all java classes that you need

    # Java classes utilisation :
    @file_input_class = Rjb::import('java.io.FileInputStream')
    @file_input = @file_input_class.new(model_file_path)
    @fs = @poifs_class.new(@file_input)
    @book = @workbook_class.new(@fs)

    @worksheet = @book.getSheet('worksheet')
    # ...
    # You can use your objects like in Java but with a ruby syntax