函数过载 合约内允许定义同名函数,但是输入参数不一致 pragma solidity ^0.4.17; contract A { function f(uint _in) public pure returns (uint out) { out = 1; } function f(uint _in, bytes32 _key) public pure returns (uint out) { out = 2; } } pragma solidity ^0.4.16; contract A { f…
View Functions 函数声明为视图,将无权修改状态 pragma solidity ^0.4.16; contract C { function f(uint a, uint b) public view returns (uint) { return a * (b + 42) + now; } } 以下操作属违规操作 1. Writing to state variables. 2. Emitting events. 3. Creating other contracts. 4. U…
输入参数 pragma solidity ^0.4.16; contract Simple { function taker(uint _a, uint _b) public pure { // do something with _a and _b. } } 输出参数 pragma solidity ^0.4.16; contract Simple { function arithmetics(uint _a, uint _b) public pure returns (uint o_sum,…
输入参数 pragma solidity ^0.4.16; contract Simple { function taker(uint _a, uint _b) public pure { // do something with _a and _b. } } 输出参数 pragma solidity ^0.4.16; contract Simple { function arithmetics(uint _a, uint _b) public pure returns (uint o_sum,…
