check existence of variable or object

Dear

I have faced a new type of problem

I pass params[:place] as POST in a url like localhost:3000/navigate

if you press on the button to navigate, it will redirect you to this
like, but if you type the link and press enter, this error will be
displayed

You have a nil object when you didn't expect it!
You might have expected an instance of ActiveRecord::Base.
The error occurred while evaluating nil.[]

I believe the whole object does not exist because i checked it using
params[:place].blank?, i still get the same error.

any idea

thanks

try:

if params[:place]

thanks
it worked