solidity合约调用合约方法的方式_solidity合约里调用合约

1. 通过接口的形式

pragma solidity >=0.7.0 <=0.8.0; 
// SPDX-License-Identifier: MIT
 
interface IRC20 {
    
    function depositEther() external payable;
 
    function withdraw(uint256 amount) external;
    
    function getBalance(address addr) external view returns(uint256);
    
}
 
contract Attack {
    
    address constant private addr = 0x78E74b14512f2f9d3C26aeE24d902Fef10F46d72;
    
    IRC20 private tract;
    
    event withdrawEth(address sender,uint256 value);
    
    constructor(){
        tract = IRC20(addr);
    }
    
     
    function despoit() public payable{
        tract.depositEther{value:2 ether}();
        tract.withdraw(1 ether);
    }
    
}

通过定义需要调用的接口，在合约构造函数里面实现加载，方法里面实现调用。以上列子在IRC20中匹配需要调用的合约接口方法。

2.通过签名的方式

pragma solidity >=0.7.0 <=0.8.0; 
// SPDX-License-Identifier: MIT
 
 
contract Test {
    
    address constant private addr = 0x78E74b14512f2f9d3C26aeE24d902Fef10F46d72;
    
    
    event balanceAmount(address sender,uint256 value);
    
    function getBalanceValue(address value) public view returns(uint256){
        bytes4 methodId = bytes4(keccak256("getBalance(address)"));
        (bool success,bytes memory data) = addr.staticcall(abi.encodeWithSelector(methodId,value));
        if(success){
            uint256 amount = abi.decode(data,(uint256));
            return amount;
        }else{
            return 0;
        }
    }
    
    
}