Generating a random number with Ruby

For my web app that I am currently building, I needed a way to generate a random item number for each new item that was posted to the site. Since I am building this app in Rails, I felt pretty sure that Ruby had a great and easy to generate a random number, and I was right.

Now, keep in mind that what I have done here does not truly generate a “random” number, as the number could in fact be generated again. However, for what I needed to do, this works just fine.

First, in my Item model I placed a simple before_create statement in:

before_create :generate_item_number

I then define that below a protected statement in order to actually generate the random number:

def generate_item_number

self.item_number= rand(9999999).to_s.center(7, rand(9).to_s)

end

This little snippet of code generates a random 7-digit number that is written to the database in the item_number column of my Item table.

If you wanted to change that to be a 10-digit number, just change the (9999999) to be 10 9’s and change the 7 that I have there to 10. Probably not the best way to go about doing this, but in my very limited Ruby/Rails knowledge, it works for me.

Share and Enjoy: