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Ruby program to check whether the hash contains specified key or not

Checking hash contains a key or not: Here, we are going to learn whether a given hash contains a specified key or not in Ruby programming language?
Submitted by Hrithik Chandra Prasad, on August 10, 2019

Checking hash contains a key or not

Given a hash and key, we have to check whether hash contains the key or not.

A hash is a collection of identical keys and their values. Hashes are the combination of integer and the object type. You can declare a hash in the following way:

    hash_name = {key_name1:value1, key_name2:value2, ...}

The existence of a key in a defined hash can be easily checked using .key? keyword.

Methods used:

• puts:
  This method is employed for putting the message on the screen for user convenience.
• .key?:
  .key? method is used to find a key within a hash. It is employed for referencing value from hash. If the key is not found it returns false, otherwise true.

Ruby code to check whether hash contains a key or not

=begin 
Ruby program to check whether a hash contains the 
specified key or not.
=end

# declaring hash 
hash={apple:1,mango:2,banana:3,orange:4,babypink:5}

#checking keys
puts hash.key?(:apple)
puts hash.key?(:one)
puts hash.key?(:orange)
puts hash.key?(:green)
puts hash.key?(:includehelp)

#checking through conditions
if(hash.key?(:apple))
    puts "hash contains the key apple"
else
    puts "hash doesnt contain the key apple"
end

if(hash.key?(:one))
    puts "hash contains the key one"
else
    puts "hash doesnt contain the key one"
end

if(hash.key?(:orange))
    puts "hash contains the key orange"
else
    puts "hash doesnt contain the key orange"
end

if(hash.key?(:green))
    puts "hash contains the key green"
else
    puts "hash doesnt contain the key green"
end

if(hash.key?(:includehelp))
    puts "hash contains the key includehelp"
else
    puts "hash doesnt contain the key includehelp"
end

Output

true
false
true
false
false
hash contains the key apple
hash doesnt contain the key one
hash contains the key orange
hash doesnt contain the key green
hash doesnt contain the key includehelp