Blockchain Development – How to Check Token Reflection Amount for Wallet Address

After a contract has called selfdestruct(), all values are set to 0. So if you have a contract like:

contract Mortal {
    address public owner;

    function Mortal() {
        owner = msg.sender;
    }

    function kill() {
        selfdestruct(owner);
    }

Then from another contract you can call:

function checkMortal(address mortal) {
    if (Mortal(mortal).owner() == 0) {
        // You know it is dead.
    } else {
        // You know it is alive.
    }
}

Update:

In newer versions of Solidity that target byzantium or later, this will likely fail. Solidity now verifies returndatasize to know if the call failed, so when owner() doesn't return anything, not even 0, it will revert the transaction. The best way to do this now is probably to use extcodesize within solidity assembly. This will only tell you it selfdestructed if you know it previously had a non-zero codesize.

I have a post explaining how to parse the Ethereum event log in detail.