solidity基础-异常

assert

contract ErrorTest {

    uint256 public balance;

    function deposit(uint256 _amount) public{
        balance = balance + _amount;
    }

    function withdraw(uint256 _amount) public{
        uint256 oldBalance = balance;
        balance = balance - _amount;
        assert(balance > oldBalance );
    }

}

部署存入25， 可以看到balance 有 25

　　　

 

 再提取 100

　　    

　输出报错