Question

pragma solidity ^0.5.3;

contract SimpleFallback{
    event FallbackCalledEvent(bytes data);
    event AddEvent(uint a, uint b, uint result);
    event DoubleEvent(uint a, uint b);
    event GetNameEvent(string);

    function() external{
        emit FallbackCalledEvent(msg.data);
    }

    function add(uint a, uint b) public returns(uint){
        // assert(a >= 0);
        // assert(b >= 0);
        // assert(a + b > a && a + b > b);

        uint _result = a + b;
        emit AddEvent(a, b, _result);

        return _result;
    }

    function double(uint a) public returns(uint){
        // assert(a >= 0);
        // assert(2*a >= 0 && 2*a >= a);
        uint _result = 2*a;

        emit DoubleEvent(a, _result);

        return _result;
    }

    function getName(string memory name) public returns(string memory){
        emit GetNameEvent(name);

        return name;
    }
}


contract RunTest{


    function callAddlTest(address other) public {
        // bytes4 messageId = bytes4(keccak256("add(uint, uint)"));
        // other.call(messageId, 5, 60);
        other.call(abi.encodeWithSignature("add(uint,uint)", 85, 60));
    }

    function callDoublelTest(address other) public {
        // bytes4 messageId = bytes4(keccak256("add(uint, uint)"));
        // other.call(messageId, 5, 60);
        other.call(abi.encodeWithSignature("double(uint)", 100));
    }

    function callgetNameTest(address other) public{
        other.call(abi.encodeWithSignature("getName(string)", "hello"));
    }
}

操作如下。

第1步：部署2个合同；
第2步。致电callAddlTest，签约SimpleFallback的地址，事件日志如下所示，这表明调用add（）失败，后备功能被触发。

[
    {
        "from": "0x038f160ad632409bfb18582241d9fd88c1a072ba",
        "topic": "0x5cd57a899be814fb3a40e18f9d1ba77420bbd22073d35165511f750aa70538b6",
        "event": "FallbackCalledEvent",
        "args": {
            "0": "0xb89663520000000000000000000000000000000000000000000000000000000000000055000000000000000000000000000000000000000000000000000000000000003c",
            "data": "0xb89663520000000000000000000000000000000000000000000000000000000000000055000000000000000000000000000000000000000000000000000000000000003c",
            "length": 1
        }
    }
]

第3步。调用callDoubleTest，签约SimpleFallback的地址，事件日志如下，这表明调用double（）失败，触发了回退功能。

[
    {
        "from": "0x038f160ad632409bfb18582241d9fd88c1a072ba",
        "topic": "0x5cd57a899be814fb3a40e18f9d1ba77420bbd22073d35165511f750aa70538b6",
        "event": "FallbackCalledEvent",
        "args": {
            "0": "0xd524bc570000000000000000000000000000000000000000000000000000000000000064",
            "data": "0xd524bc570000000000000000000000000000000000000000000000000000000000000064",
            "length": 1
        }
    }
]

第4步。致电callgetNameTest，签约SimpleFallback的地址，事件日志如下，这表明成功调用了getName（）。


    {
        "from": "0x038f160ad632409bfb18582241d9fd88c1a072ba",
        "topic": "0x26c73f7f14382f5db0b9f94dd29ff8938f2e4be69fb13e0825ece287e8e538d5",
        "event": "GetNameEvent",
        "args": {
            "0": "hello",
            "length": 1
        }
    }
]

问题：呼叫（abi.encodeWithSignature（）），原因：

1）other.call(abi.encodeWithSignature("add(uint,uint)", 85, 60));无效？
2）other.call(abi.encodeWithSignature("double(uint)", 100));无效？
3）other.call(abi.encodeWithSignature("getName(string)", "hello"));起作用了吗？
4）1）和3）比较，abi.encodeWithSignature不支持多个参数吗？并比较2）和3）abi.encodeWithSignature不支持uint参数吗？

Answer 1

我已经找到了根本原因。它应该使用类型的全名而不是别名，因此应为uint256而不是uint。

solidity abi.encodeWithSignature不适用于diffienet参数

1 个答案: