我是区块链技术的新手,并试图从互联网上到处了解一些东西(Etheruem、Truffle、DApps 等)。来自以太坊官网,
我正在尝试具体了解这些功能
approve(address _spender, uint _value) returns (bool success) {...}
approveAndCall(address _spender, uint _value, bytes _extraData) returns (bool success) {...}
transferFrom(address _from, address _to, uint _value) returns (bool success) {...}
最后这个function() {throw;}
本合约代码
合约代币收件人{ 函数receiveApproval(地址_from,uint_value,地址_token,字节_extraData); }
和这个宣言mapping (address => mapping (address => uint) ) public allowance;