JS: Define Function

By Xah Lee. Date: . Last updated: .

Create a Function

There are 3 ways to create a function.

  1. By the keyword function.
  2. By Arrow Function expression. Most simple. [see JS: Arrow Function]
  3. By constructor with keyword Function. [see JS: Function Constructor]

Keyword β€œfunction”

The syntax is:

function name (parameters) {body_statements}

Return Statement

In the function body, you can have 0 or more return expr.

When program reaches the return statement, it'll exit the function, and return the value.

Function without return statement returns the value undefined.

for detail, see JS: Function Parameters and other pages.

JavaScript, Function

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