selfestruct() in soldity

Question

Hey I'm trying to use selfdestruct in solidity but I'm getting this error when I'm trying to run selfdestruct(address*) :

TypeError: Invalid type for argument in function call. Invalid implicit conversion from int_const 0 to address payable requested. --> contracts/Hello_World.sol:9:22: | 9 | selfdestruct(0x0); | ^^^

*address- my Ethereum address

The code :

pragma solidity >=0.7.0 <0.9.0; 
contract HelloWorld { 
string public message; 
function setMessage(string memory newMessage) public { 
message = newMessage; 
} 

function remove() public {
 selfdestruct(0x0); 
} 
}

Answer 1

Apparently you're passing a constant integer to selfdestruct, while the correct call would be to pass an address. 0x0 is not the 0 address, it's just the hexadecimal form of the integer 0. You need to convert it into a payable address and pass it to selfdestruct as follows:

selfdestruct(payable(0x0))

Actually, you don't even need to use the hex format and you could just use the decimal format as follows:

selfdestruct(payable(0))

Note: casting as payable only works in Solidity versions >=0.6.0.

By the way, what this call does is burn any ETH contained in that contract upon destruction. Make sure that this is what you want to do.