Solidity：合约调用另一个合约，地址不同，为什么？答案

【问题标题】：Solidity: contract calling another contract and addresses are different, why?Solidity：合约调用另一个合约，地址不同，为什么？
【发布时间】：2018-02-04 12:18:06
【问题描述】：

我有一个包装合同实例化并调用另一个合同，我的测试用例显示所有者 (msg.sender) 不匹配。为什么？

合同A

pragma solidity ^0.4.4;

contract A {

    address public owner;

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

    function createB(string name) {
        return new B(msg.sender, name);
    }
}

合约B

pragma solidity ^0.4.4;

contract B {
    address public owner;
    string public name;

    function B(address _owner, string _name) {
        owner = _owner;
        name = _name;
    }
}

测试用例

pragma solidity ^0.4.0;

import "truffle/Assert.sol";
import "truffle/DeployedAddresses.sol";
import "../contracts/B.sol";

contract TestB {
    B testB;
    A testA;

    function beforeEach() {
        A = A(DeployedAddresses.A());
        B = testA.createB("test");
    }

    function testOwnerIsSet() {
        Assert.equal(address(A), address(B), "Owner's address does not match");
    }
}

测试结果

 1) TestB testOwnerIsSet:
     Error: Owner's address does not match
      at /Users/xxx/.config/yarn/global/node_modules/truffle/build/cli.bundled.js:214233:17
      at Array.forEach (native)
      at processResult (/Users/xxx/.config/yarn/global/node_modules/truffle/build/cli.bundled.js:214231:19)
      at process._tickCallback (internal/process/next_tick.js:109:7)

编辑

我已将address public owner 添加到contract A。并在contract B 中公开owner。

现在我的 TestB 合约看起来像这样：

pragma solidity ^0.4.0;

import "truffle/Assert.sol";
import "truffle/DeployedAddresses.sol";
import "../contracts/B.sol";

contract TestB {
    B testB;
    A testA;

    function beforeEach() {
        A = A(DeployedAddresses.A());
        B = testA.createB("test");
    }

    function testOwnerIsSet() {
        address aOwner = A.owner();
        address bOwner = B.owner();
        Assert.equal(aOwner, bOwner, "Owner's address does not match");
    }
}

【问题讨论】：

标签： ethereum contract solidity

【解决方案1】：

根据您所展示的内容，我假设您使用的是松露？老实说，我很惊讶它能编译。

当你打电话时，

B = testA.createB("test");

您从TestB 调用它。 msg.sender 将是TestB 的地址。

function createB(string name) {
    return new B(msg.sender, name); // msg.sender = TestB instance address
}

This 可能有助于实现您的目标。

【讨论】：