What is the member?() method of hash in Ruby?
Overview
In Ruby, the member?() method of a hash is used to check if a certain key value is present in the hash.
Syntax
hash.member?(key)
Parameters
This method takes the parameter, key, which represents the key we want to check in the hash.
Return value
It returns a boolean value; true if the key exists and false if it doesn’t.
Example
# create some hashesh1 = {one: 1, two: 2, three: 3}h2 = {name: "okwudili", stack: "ruby"}h3 = {"foo": 0, "bar": 1}h4 = {M:"Mango", A: "Apple", B: "Banana"}# check if some keys existsputs h1.member?(:one)puts h2.member?(:stack)puts h3.member?(:bar)puts h4.member?(:D)
Explanation
- Line 2–5: We create the hashes
h1,h2,h3, andh4. - Line 8–11: We use the
member?()method to check if some keys exist in the hashes. Next, we print the results to the console.