JavaScript strings

A String in JavaScript consists of consecutive alphanumeric characters, which includes:

• letters
• digits (not to be confused with numbers)
• whitespace
• punctuation
• special characters
• emoji (even these!)

We also encapsulate strings with quotation marks (either with 'single quotes' or "double quotes").

A string can consist entirely of numeric characters but it does not make it a number: if we have two strings, 2 and 2 , and we add them together, they will become 22, not 4!

Concatenating strings

In the console, we can test the following using + on a set of strings:

1console.log("I" + " " + "am" + " " + "learning!")
2// I am learning!

We can also join strings using the concat() method (a built-in command), by listing them out inside the brackets:

1console.log(concat("I", " ", "am", " ", "learning!"))
2// I am learning!

String variables

So why was that important? Why couldn't we simply type "I am learning!"?

Well, later on, when we wish to gather longer samples of text from different sources, we may wish to store them into different variables.

To create a string variable in JavaScript:

• we use the const keyword
• followed by a space
• give the variable a name
• followed by a space, an equal sign, and another space
• place the string with the quotation marks

The concat() method then allows us to effortlessly combine multiple variables together:

1// our variables
2const x = "This is a long piece of text from one source!"
3const y = "This is a longer piece of text from another source!"
4const z = "I don't know where this came from but it must be true!"
5
6// this will output all text in the variables above
7// each variable is separated by a space
8console.log(concat(x, " ", y, " ", z)

We can then easily change the text in variables, rather than in the console.log line of code!