My withdraw function doesn't work

Question

Writing my first contract using YouTube courses all around. On the step to create a withdraw function get receive the money back.

Here is the code below. Not sure where I went wrong.

function withdraw() payable public {
    msg.sender.transfer(address payable(this).balance);
    

//Type error send and transfer are only available for objects of type address payable

Answer 1

You get this error because msg.sender is of type address by default and not address payable (since solidity 0.8.0).

A type address doesn't have access to those functions (send / transfer) , but a type of address payable does.

Try like this :

function withdraw() public {
    payable(msg.sender).transfer(address(this).balance);
}

Btw, I removed the payable modifier to the withdraw function since it makes little sense to send money as you'd get it back instantly.