Let’s say we have a variable, text, assigned to a string:

let text = "the cat sat on the mat";

We want to replace the word “the” with the word “no”.

A JavaScript string has a nice [replace](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replace) method that we can use to do this. So, let’s give this a try:

text = text.replace("the", "no");

The text variable now contains the value “no cat sat on the mat”. This perhaps isn’t what we’d hoped for - only the first “the” has been replaced.

The first, parameter in the replace method can actually be a regular expression which we can use to specify that we want to replace all the instances of the matched word:

text = text.replace(/the/g, "no");

The g at the end of the regular expression tells the replace method to match all instances.

So, the text variable now contains the value “no cat sat on no mat”. Great - we managed to replace all the instances of “the” with “no”!

#javascript #programming