How to cycle through an instance

Ruby
1

Hi there,

I’m sorry for this noob question (but at least it must be a quick one
for you guys):

I have an instance of an object in my database and need to get out every
element of it, like this:

Example: model = student

firstname = Fred
lastname = Williams
streetname = NULL
city = NULL
date of birth = 12.12.1934
…
(until there is no more column name left for this model)

How do I correctly/efficiently cycle through this one?

Thank you very much for your help!
Tom

2

Tom Ha wrote:

I have an instance of an object in my database and need to get out every
element of it, like this:

Example: model = student

firstname = Fred
lastname = Williams
streetname = NULL
city = NULL
date of birth = 12.12.1934
…
(until there is no more column name left for this model)

How do I correctly/efficiently cycle through this one?

Depends on what ORM you are using.

If it’s ActiveRecord, try obj.attributes

(ActiveRecord questions probably best asked on the Rails mailing list
though)

3

Thanks a lot !

4

Have you try something like this:

@student = Student.find(params[:id])

@student.attribute_names.each do |attr_name|
puts “#{attr_name} => #{@student.attribute[attr_name]}\n”
end

or

puts @student.attribute_names.map { |attr_name| “#{attr_name} => #
{@student.attribute[attr_name]}”}.join("\n")

5

Cool, thanks a bunch!