This is how to convert a string to a class in Rails/Ruby:
p = "Post"
Kernel.const_get(p)
eval(p)
p.constantize
But what if I am retrieving a column from an array/active record object like:
Post.description
but it could be
Post.anything
where anything is a string like anything = "description"
How can I make it work? Any ideas. This is helpful since I want to refactor a very large class and reduce lines of code and repetition.
Many thanks.
While eval can be a useful tool for this sort of thing, and those from other backgrounds may take to using it as often as one might a can opener, it's actually dangerous to use so casually. Eval implies that anything can happen if you're not careful.
A safer method is this:
on_class = "Post"
on_class.constantize.send("method_name")
on_class.constantize.send("method_name", arg1)
Object#send will call whatever method you want. You can send either a Symbol or a String and provided the method isn't private or protected, should work.
Hi
try this
class Test
def method_missing(id, *args)
puts id - get your method name
puts args - get values
end
end
a = Test.new a.name('123')
so the general syntax would be a.()
hope this helps
cheers
sameera