JavaScript – Convert Function to String and Back

This post demonstrates how to convert a JavaScript function to string and using the same string to declare and execute a new method dynamically.

Using Plunker

Plunker is an online web site that allows programmers to create client-side JavaScript code snippets for demonstration, issue replication, or Proof-of-Concepts (POCs).

My Plunker

To access my JavaScript code snippet available on Plunker, please access the following URL:


Notice the contents under the Console tab on the right side. First, the function’s definition is displayed. Then, that definition is used twice displaying “This is myFunction” twice.

There are 2 important files to get things working.

  • index.html
  • script.js

By the way, I am using Google Chrome to access Plunker.

Using Node.js

Node.js allows you to create and execute server-side codes. We’ll not discuss about Node.js but I assume you have it installed in your system.

Download the script.js from my Plunker, and run it on the Windows command-line prompt.

The JavaScript Code Snippet

The script.js file used in both Plunker and Node.js has the following codes.

Code to Convert a Function to String

To convert a function to string, use the toString() method of a function object.

Codes to convert string to a function


Karl San Gabriel

Karl San Gabriel

Java and Enterprise Technologies Expert