How to check if a specific key is present in a hash or not?

ruby data-structures associative-array
Mohit Jain picture Mohit Jain · Dec 24, 2010 · Viewed 444.7k times · Source

I want to check whether the "user" key is present or not in the session hash. How can I do this?

Note that I don't want to check whether the key's value is nil or not. I just want to check whether the "user" key is present.

Answer

sepp2k picture sepp2k · Dec 24, 2010

Hash's key? method tells you whether a given key is present or not.

session.key?("user")

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