else structure in Ruby

I have written something like this, the same if-else logic I knew from Visual Basic 6.0, but I am sure there is a better "Ruby way" of writing it.

Can you please show me how it would look like in Ruby world?

  if params[:medication_name].nil?
    med_name = 'all'
  elsif params[:medication_name] == 'undefined'
    med_name = 'all'
  else
    med_name = params[:medication_name]
  end

---

For your case, something like this:

med_name = params[:medication_name] 
med_name = 'all' if [nil, 'undefined'].include? med_name

For more general long chains of if / elsif / else , look at case statements. They're overkill in this case, but here's an example:

med_name = case params[:med_name]
   when 'undefined', nil 
     'all'
   else
      params[:med_name]
end

---

有几种不同的方法可以简化这一点，例如：

med_name = params[:medication_name]
med_name = 'all' if med_name.nil? or med_name == 'undefined'

---

Ruby独有：

med_name = {nil=>'all', 'undefined'=>'all'}[params[:medication_name]] || params[:medication_name]

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