Strings
Strings are values made up of text and can contain letters, numbers, symbols, punctuation, and even emoji.
Strings are contained within a pair of either single quotation marks '' or double quotation marks "".
| EXAMPLE |
|---|
| 'This is a string. 👏'; "This is the 2nd string. 💁"; |
Enclosing quotation marks
Let’s say you’re trying to use quotation marks inside a string. You’ll need to use opposite quotation marks inside and outside. That means strings containing single quotes need to use double quotes and strings containing double quotes need to use single quotes.
| EXAMPLE |
|---|
| "It's six o'clock."; 'Remember to say "please" and "thank you."'; |
Alternatively, you can use a backslash \ to escape the quotation marks. This lets JavaScript know in advance that you want to use a special character.
Here’s what that looks like reusing the examples above:
| EXAMPLE |
|---|
| 'It\'s six o\'clock.'; "Remember to say \"please\" and \"thank you.\""; |
Properties and methods
Strings have their own built-in variables and functions, also known as properties and methods. Here are some of the most common ones.
length
A string’s length property keeps track of how many characters it has.
| EXAMPLE |
|---|
| "caterpillar".length; |
| OUTPUT |
| 11 |
toLowerCase
A string’s toLowerCase method returns a copy of the string with its letters converted to lowercase. Numbers, symbols, and other characters are not affected.
| EXAMPLE |
|---|
| "THE KIDS".toLowerCase(); |
| OUTPUT |
| "the kids" |
toUpperCase
A string’s toUpperCase method returns a copy of the string with its letters converted to capitals. Numbers, symbols, and other characters are not affected.
| EXAMPLE |
|---|
| "I wish I were big.".toUpperCase(); |
| OUTPUT |
| "I WISH I WERE BIG." |
trim
A string’s trim method returns a copy of the string with beginning and ending whitespace characters removed.
| EXAMPLE |
|---|
| " but keep the middle spaces ".trim(); |
| OUTPUT |
| "but keep the middle spaces" |