Question

I try to use the ruby standard csv lib to dump out the arr of object to a csv.file , called ‘a.csv’

http://ruby-doc.org/stdlib-1.9.3/libdoc/csv/rdoc/CSV.html#method-c-dump

dump(ary_of_objs, io = "", options = Hash.new)

but in this method, how can i dump into a file?
there is no such examples exists and help. I google it no example to do for me…

Also, the docs said that…

The next method you can provide is an instance method called
csv_headers(). This method is expected to return the second line of
the document (again as an Array), which is to be used to give each
column a header. By default, ::load will set an instance variable if
the field header starts with an @ character or call send() passing the
header as the method name and the field value as an argument. This
method is only called on the first object of the Array.

Anyone knows how to pass the instance method csv_headers() to this dump function?

Answer 1

I haven’t tested this out yet, but it looks like io should be set to a file. According to the doc you linked “The io parameter can be used to serialize to a File”

Something like:
f = File.open("filename")
dump(ary_of_objs, io = f, options = Hash.new)