如何獲得類似於“混音”的“事件日誌”？

May 8, 2018

我有一個事件如下：

event LogNewObject(address sender, bytes32 indexed id, bytes32 sub_states_types, bytes32 sub_states_values, address owner);

此事件用於以下功能：

function newObject(bytes32 _id, uint256 number_of_sub_states, bytes32[10] sub_states_types, bytes32[10] sub_states_values, address _owner) public returns(bool success) {
       require(!isObject(_id));

       uint256 counter=0;
       for(counter; counter &lt; number_of_sub_states; counter++) {

           objectStructs[_id].state.sub_state[sub_states_types[counter]] = sub_states_values[counter];

           emit LogNewObject(msg.sender, _id, bytes32(sub_states_types[counter]), bytes32(sub_states_values[counter]), _owner);

       }

       objectStructs[_id].owner = _owner;
       objectStructs[_id].isObject = true;

       objectList.push(_id);

       return true;
   }

我想得到像remix這樣的日誌，如下圖所示：

但是，當我使用以下程式碼獲取事件日誌時：

var Ev = contractInstance.LogNewObject({}, {fromBlock: 0, toBlock: 'latest'});
      Ev.get((error, events) =&gt; {
      if (!error) {
         function ShowResults(event) {
           console.log('sub_states_types: ' + event.args.sub_states_types);
           console.log('sub_states_values: ' + event.args.sub_states_values);
           }
         events.forEach(ShowResults);
       } else {
       console.log('Error');
         }
       });

我收到以下錯誤：

TypeError：contractInstance.LogNewObject 不是函式

如上圖所示，我如何呼叫event LogNewObject以獲得像remix logs 輸出一樣的結果？

注意：我根據使用者“oktapodia”的回答修改了我的命令。第一個 spep 現在沒有錯誤，但是我收到另一個錯誤，如下所示：

> var Ev = contractInstance.events.LogNewObject({}, {fromBlock: 0, toBlock: 'latest'});
undefined
>        Ev.events.get((error, events) =&gt; {
...        if (!error) {
.....           function ShowResults(event) {
.......             console.log('sub_states_types: ' + event.args.sub_states_types);
.......             console.log('sub_states_values: ' + event.args.sub_states_values);
.......             }
.....           events.forEach(ShowResults);
.....         } else {
.....         console.log('Error');
.....           }
...         });
TypeError: Cannot read property 'get' of undefined

如果我使用以下格式，我會再次收到以前的錯誤：

> var Ev = contractInstance.events.LogNewObject({}, {fromBlock: 0, toBlock: 'latest'});
undefined
>        Ev.get((error, events) =&gt; {
...        if (!error) {
.....           function ShowResults(event) {
.......             console.log('sub_states_types: ' + event.args.sub_states_types);
.......             console.log('sub_states_values: ' + event.args.sub_states_values);
.......             }
.....           events.forEach(ShowResults);
.....         } else {
.....         console.log('Error');
.....           }
...         });
TypeError: Ev.get is not a functionI also used the command proposed by user "oktapodia", however I receive this error :

我還使用了該命令，因為他的回答中解釋了使用者“oktapodia”。但是我收到如下新錯誤：“TypeError：無法讀取未定義的屬性’LogNewObject’”

重要提示：這是我的智能合約程式碼：

pragma solidity 0.4.23; 

contract RFID {

   struct StateStruct {
       bytes32 description;
       mapping(bytes32 =&gt; bytes32) sub_state;
   }

   struct ObjectStruct {
       StateStruct state;
       address owner; 
       bool isObject;
   }

   mapping(bytes32 =&gt; ObjectStruct) objectStructs;
   bytes32[] public objectList;

   event LogNewObject(address sender, bytes32 indexed id, bytes32 sub_states_types, bytes32 sub_states_values, address owner);
   event LogChangeObjectState(address sender, bytes32 indexed id, bytes32 sub_states_types, bytes32 sub_states_values);
   event LogChangeObjectOwner(address sender, bytes32 indexed id, address newOwner);

   function isObject(bytes32 _id) public view returns(bool isIndeed) {
       return objectStructs[_id].isObject;
   }

   function getObjectCount() public view returns(uint count) {
       return objectList.length;
   }

   /*function setArraySize(uint256 _number_of_sub_states) public {

       number_of_sub_states = _number_of_sub_states;

   }

   function getArraySize() view public returns (uint256) {
      return number_of_sub_states;
   }*/

   function newObject(bytes32 _id, uint256 number_of_sub_states, bytes32[10] sub_states_types, bytes32[10] sub_states_values, address _owner) public returns(bool success) {
       require(!isObject(_id));

       uint256 counter=0;
       for(counter; counter &lt; number_of_sub_states; counter++) {

           objectStructs[_id].state.sub_state[sub_states_types[counter]] = sub_states_values[counter];

           emit LogNewObject(msg.sender, _id, bytes32(sub_states_types[counter]), bytes32(sub_states_values[counter]), _owner);

       }

       objectStructs[_id].owner = _owner;
       objectStructs[_id].isObject = true;

       objectList.push(_id);

       return true;
   }

   function changeObjectState(bytes32 _id, uint256 number_of_sub_states, bytes32[10] sub_states_types, bytes32[10] sub_states_values) public returns(bool success) {
       require(isObject(_id));
       uint256 counter=0;
       for(counter; counter &lt; number_of_sub_states; counter++) {

           objectStructs[_id].state.sub_state[sub_states_types[counter]] = sub_states_values[counter];

           emit LogChangeObjectState(msg.sender, _id, bytes32(sub_states_types[counter]), bytes32(sub_states_values[counter]));

       }
       //objectStructs[_id].state = StateStruct(_newState);
       //emit LogChangeObjectState(msg.sender, _id, _newState);
       return true;
   }

   function changeObjectOwner(bytes32 _id, address _newOwner) public returns(bool success) {
       require(isObject(_id));
       objectStructs[_id].owner = _newOwner;
       emit LogChangeObjectOwner(msg.sender, _id, _newOwner);
       return true;
   }

}

function newObject並使用以下命令呼叫：

contractInstance.methods.newObject(web3.utils.asciiToHex("50"),3,[web3.utils.asciiToHex("location"),web3.utils.asciiToHex("price"),web3.utils.asciiToHex("sold"),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex("")],[web3.utils.asciiToHex("Paris"),web3.utils.asciiToHex("50"),web3.utils.asciiToHex("No"),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex(""),web3.utils.asciiToHex("")], '0xE07b6e5a2026CC916A4E2Beb03767ae0ED6af773').send({ from: '0xE07b6e5a2026CC916A4E2Beb03767ae0ED6af773' }, function(error, result) {
   console.log(error);
   console.log(result)
});

看起來您正在使用具有新語法的 web3 1.0 版（此處的文件）
更改contractInstance.LogNewObject為contractInstance.events.LogNewObject

答案太長，無法在單個評論中添加。
因為您是直接在終端中而不是從文件中執行它，所以在 NodeJS 中，分號不是強制性的，並且您的終端將解釋.on為新範圍內的新行而不是函式 bind to contractInstance.events.LogNewObject，以下範例應直接從你的終端，但不是很漂亮:)
contractInstance.events.LogNewObject({
 fromBlock: 0,
}, function(error, event){ console.log(event); }).on('data', function(event){
   console.log(event); // same results as the optional callback above
 }).on('changed', function(event){
   // remove event from local database
 }).on('error', console.error);

引用自：https://ethereum.stackexchange.com/questions/47751

如何獲得類似於“混音”的“事件日誌”？

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