• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar

The Programming Expert

Solving All of Your Programming Headaches

  • HTML
  • JavaScript
  • jQuery
  • PHP
  • Python
  • SAS
  • Ruby
  • About
You are here: Home / Ruby / Ruby has_key Method – Check if Hash Has Key

Ruby has_key Method – Check if Hash Has Key

October 18, 2022 Leave a Comment

The Ruby has_key? method simply checks to see if a hash has a specific key or not. If it does, true will be returned. If the key is not found, false will be returned.

some_hash = {"first_name" => "David", "last_name" => "Smith"}

puts some_hash.has_key? "first_name"

#Output
true

The has_key? method is pretty straightforward but can be really useful when trying to find information stored in a hash.

Let’s look at some more examples of the has_key? method.

some_hash = {"id" => "1", "first_name" => "David", "last_name" => "Smith", "age" => "45"}

puts some_hash.has_key? "first_name"
puts some_hash.has_key? "David"
puts some_hash.has_key? "last_name"
puts some_hash.has_key? "age"
puts some_hash.has_key? ""

#Output
true
false
true
true
false

Let’s take a look at the has_value? method in Ruby to get the other values in our hash.

Check If Value Exists in Hash Using the Ruby has_value? Method

We looked at the has_key? method above to see if a certain key was contained in our hash. Now we can use the has_value? method to see if certain values are contained in our hash.

some_hash = {"first_name" => "David", "last_name" => "Smith"}

puts some_hash.has_value? "David"

#Output
true

Let’s run the same examples above, but this time check for certain values that might be contained in the hash.

some_hash = {"id" => "1", "first_name" => "David", "last_name" => "Smith", "age" => "45"}

puts some_hash.has_value? "first_name"
puts some_hash.has_value? "David"
puts some_hash.has_value? "last_name"
puts some_hash.has_value? "45"
puts some_hash.has_value? 45

#Output
false
true
false
true
false

Hopefully this article has been useful for you to learn how to the Ruby has_key? method works.

Other Articles You'll Also Like:

  • 1.  Using Ruby to Capitalize First Letter of Each Word
  • 2.  Using Ruby to Create List of Prime Numbers
  • 3.  Ruby Floor – Find Floor of Number with floor Method
  • 4.  Using Ruby to Get the Length of a String
  • 5.  Using Ruby to Get the Length of Array
  • 6.  Get the Sum of an Array in Ruby
  • 7.  Ruby String Comparison
  • 8.  Using Ruby to Convert String to Array
  • 9.  Ruby puts vs print
  • 10.  Ruby unshift Method – Add Items to Start of Array

About The Programming Expert

The Programming Expert is a compilation of a programmer’s findings in the world of software development, website creation, and automation of processes.

Programming allows us to create amazing applications which make our work more efficient, repeatable and accurate.

At the end of the day, we want to be able to just push a button and let the code do it’s magic.

You can read more about us on our about page.

Reader Interactions

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Primary Sidebar

About The Programming Expert

the programming expert main image

Welcome to The Programming Expert. We are a group of US-based programming professionals who have helped companies build, maintain, and improve everything from simple websites to large-scale projects.

We built The Programming Expert to help you solve your programming problems with useful coding methods and functions in various programming languages.

Search

Learn Coding from Experts on Udemy

Looking to boost your skills and learn how to become a programming expert?

Check out the links below to view Udemy courses for learning to program in the following languages:

Copyright © 2023 · The Programming Expert · About · Privacy Policy