Imagine a scenario where you’re dealing with an HTML form with text boxes where you are passing the data to the back end by using JavaScript methods. If a user enters a single quote or a double quote in the textbox, the JavaScript could go bonkers having not being properly validated.

There is a simple fix for that: Replace the quotes with Character codes.

The double quote (“) has a Character code \x27 and for the single quote (‘) \x22. So to fix this, you add this code.

var txt = f.txt.value.replace(/\'/,'\x27').replace(/\"/,'\x22');

This replaces the characters with char codes in the textbox called txt in the form named f and assigns to the var txt. (I used JQuery to get values of the txt.. That’s JQuery notation. But you can also use vanilla JS for this) You can find another use/example here