Strings

Introduction

We've already seen strings several times! Let's cover them in more detail. Checkout the String Documentation. Bookmark this page! Look at the "Methods" column on the left-hand side.

What is a string?

A String is an object that represents a sequence of characters in ruby. Strings can contain anything: letters, numbers, special characters... Here are some examples of strings:

• "Hello, World!"
• "123456"
• "!@#$%^&"

How to make a string

We can make a string by enclosing a sequence of characters in either single ('') or double ("") quotes. These operate identically, with one important difference, interpolation. We'll talk about this more later. It's convenient to have two options for making strings for the following reason:

Let's say we want to make a string that looks like this:

phrase = 'This isn't ice cream!'

Or maybe..

other_phrase = "Billy says "I love ruby" a lot."

Neither of the above code snippets are valid because we're trying to use quotation marks inside the string and ruby is getting confused! Let's use one type of quotation to enclose a string that contains the other type:

phrase = "This isn't ice cream!"
other_phrase = 'Billy says "I love ruby" a lot.'

Much better :)

Concatenation & interpolation

Let's say I have two strings and I want to combine them into one:

greeting = "Why, hello there "
name = "Grace"

I could do so using string concatenation:

greeting = "Why, hello there "
name = "Grace"

puts greeting + name

Test this in pry!

This works well when the two strings are combined one after another. But what if I want to insert one string somewhere in the middle of another? This is where we'll want to use interpolation. An important note:

interpolation only works with double quoted strings!

name = "Yi"

puts "Why, hello there #{name}! Have a nice day!"

Test this in pry!

Note that you must use the following symbols: #{..} whatever ruby code is contained inside the curly braces is interpolated into the string. Here's another example:

puts "5 + 7 is #{5 + 7}"

Useful Methods

Indexing & Slicing

Watch the video!

Try this in pry!

Other Useful Methods