I'm looking for a elegant way to assign the value stored inside an Hash into a pre-existed object. Just to be clear, if I have an object, say obj with two attributes, say name and age, I want to assign this values coming from an hash without do something like:
obj.name = hash[:name]
obj.age = hash[:age]
Thanks for your attention. Simone
Best bet is probably to simply define a method like update_attributes which takes a hash and does it inside an instance method of the class.
Expanding on what others have written and what you seem to need I think your best bet would be:
hash.keys.each do |key|
m = "#{key}="
obj.send( m, hash[key] ) if obj.respond_to?( m )
end
This will account for:
Using instance_variable_set is another option. Here is an example:
class Test; attr_accessor :name, :age; end
hash = {name: 'John', age: 52}
obj = Test.new
hash.each do |k,v|
obj.instance_variable_set("@#{k}".to_sym, v) # :name is converted to :@name
end
p obj # => #<Test:0x007fd8cbb75b00 @name="John", @age=52>
The only trick is that instance_variable_set expects a symbol starting with @ so :@name is valid but :name is not.