Ruby on rails用f.select下拉数组

Question

I have an array like this:

@array = [[1, a], [2, b], [3, c] ............]

i want to create a drop down in my view with an

f.select 

the drop down should have only the numbers ie, [1, 2, 3, ....]

How can i create a drop down with only the numbers and an f.select in my view?

Answer 1

这样的事情会起作用：

@array.collect{|x| x[0]}

Answer 2

Just use. It is very easy to implement.

select(:person, :city_id, [['Lisbon', 1], ['Madrid', 2], ...])

or

f.select(:city_id, [['Lisbon', 1], ['Madrid', 2], ...])

Notice that the third parameter, the options array, is the same kind of argument you pass to options_for_select. One advantage here is that you don't have to worry about pre-selecting the correct city if the user already has one — Rails will do this for you by reading from the @person.city_id attribute.