How to use a function as value in Session storage

Question

I want to trigger a function while calling a particular key stored in Session Storage.

I tried the code given below.

sessionStorage.setItem('user', function myfync{alert("Hi")});

But while using the getItem function it is returned to me as a string and the function does not get executed. Is there a workaround to this that I'm missing?

Answer 1

Sessionstorage (and localstorage) only support strings as values.

This means you have to convert the value into a string before you store it and convert it back after reading it.

This can be done using String() and Function().

Example:

// Write
const a = function myfunc() {
    alert("Hi");
};
sessionStorage.setItem('user', String(a));

// Read
const b = sessionStorage.getItem('user');
const c = Function('return ' + b);

//Execute
c();

Converting a string back to a function is a debatable topic, more info can be found here: Is there a way to create a function from a string with javascript?