Daniel Matthew

Strings in JavaScript

Escape Characters

There are some useful ways to format strings in JavaScript:

  • A literal backslash would be written as \\
  • To start a new line, \n
  • To insert a tab, we use \t

Concatenating Strings

It's possible to join two (or more strings) like so:

var hello = "Hello ";
var world = "world!";

var helloWorld = hello + world;

This technique is useful for being able to break one long string over several lines for ease of editing:

var longString = "Hello, this could be a " +
  "rather long string if " +
	"allowed to run on one " +
	"line."

Methods

JavaScript's String class gives us a healthy number of methods that allow us to manipulate them. These include:

Method Use
length A property to describe the length of the string
indexOf() Allows us to discover where a particular string exists
charAt(index) Used to discover the character at the specified index. Don't forget indexes are zero-based!
substr(start, length) Returns a snippet of the original string
toLowerCase() Returns a new string that is all lower case.
toUpperCase() Returns a new string that is in upper case.

Comparing Strings

By calculating the ASCII values of each character, JavaScript can help us determine if one string is equal to another.

var first = "Hello";
var second = "hello";

if (first === second) {
  console.log('Strings are equal');
} else {
  console.log('Strings are different');
}

Daniel is a front-end developer at Talis, with an interest in accessibility, performance, and web components.