How do you use Ruby CSV converters?

Question

Suppose you have the following file:

textfield,datetimefield,numfield
foo,2008-07-01 17:50:55.004688,1
bar,2008-07-02 17:50:55.004688,2

The Rub

Answer 1

Works!!! Executable version of code:

#Define test data
src =
  "textfield,datetimefield,numfield\n" +
  "foo,2008-07-01 17:50:55.004688,1\n" +
  "bar,2008-07-02 17:50:55.004688,2"

require 'csv'
require 'time'

CSV::Converters[:mytime] = lambda{|s|
  begin
    Time.parse(s)
  rescue ArgumentError
    s
  end
}

csv = CSV(src, :headers => true, :converters => [:mytime])
array_of_hash_objects = csv.to_a.map {|row| row.to_hash }

array_of_hash_objects.each do |row|
  print "#{row}"
  the_date = row['datetimefield'].to_date
  puts
  print the_date
  puts
end

CSV::Converters[:time2date] = lambda{|s|
  begin
    Time.parse(s).to_date
  rescue ArgumentError
    s
  end
}

csv = CSV(src, :headers => true, :converters => CSV::Converters.keys + [:time2date])
array_of_hash_objects = csv.to_a.map {|row| row.to_hash }

array_of_hash_objects.each do |row|
  print "#{row}"
  puts
  p row['datetimefield'] #Date-field
end

=============

Outputs:

{"textfield"=>"foo", "datetimefield"=>2008-07-01 17:50:55 -0400, "numfield"=>"1"}
2008-07-01
{"textfield"=>"bar", "datetimefield"=>2008-07-02 17:50:55 -0400, "numfield"=>"2"}
2008-07-02
{"textfield"=>"foo", "datetimefield"=>2008-07-01 17:50:55 -0400, "numfield"=>1}
2008-07-01 17:50:55 -0400
{"textfield"=>"bar", "datetimefield"=>2008-07-02 17:50:55 -0400, "numfield"=>2}
2008-07-02 17:50:55 -0400