Strings are a data type that contain a sequence of letters, numbers, symbols, and whitespace. However, sometimes we need to access an individual character, or just a few characters, of a string. Thankfully Ruby provides a simple and straightforward way for doing so.
Before we get into how to access the character(s) of a string, it is important to understand an underlying concept of strings. Similar to an array, each character in a string has an index number, starting with 0. So for example in the string:
my_string = "String"
each character’s corresponding index would be:
S: 0 t: 1 r: 2 i: 3 n: 4 g: 6
With this knowledge in hand, we can now proceed to accessing piece(s) of the string as needed. To do so, we will be leveraging Ruby’s slice() method. For example:
my_string = "String"
my_string.slice(0)
>>> "S"
Or if we wanted to access multiple characters, we pass a range of indices to slice():
my_string = "String"
my_string.slice(2..6)
>>> "ring"
Additionally we can use negative indices to work backwards from the end of the string. For example:
my_string = "String"
my_string.slice(-1)
>>> "g"
my_string.slice(-3)
>>> "i"
With this knowledge in hand, we can easily access individual characters or groups of characters of a string in Ruby with ease.