Reactjs 从Web.js连接到Solidity contract时地址无效

**根据评论更新

当与契约交互并直接使用“契约地址：”从块菌迁移输出直接调用函数时，错误也是无效地址

  loadDataContract = () =>  {

      const contract = TruffleContract(DataAccess)
      contract.setProvider(this.web3Provider)
      contract.defaults({from: this.web3Provider});


      // initial function
      contract.at('0x8a4A12479486A427109e964e90CaEB5798C13A01').enroll().then((Output) => {
        this.setState({value: Output})
      }).catch(err => console.log("Enroll function error ", err))

    };

-

刚接触Solidity contracts和web3.js（尽管我已经尝试了好几个星期了！！）

我正在使用react.js、truffle contract和web3创建一个Dapp，并从Ganache连接到我的智能合约。我还通过网页包管理我的应用程序

我已经用Solidity（如下所示的版本）编写了一份简单的合同，并且可以从truffle控制台毫无问题地连接到合同

当通过一个简单的（对于本演示）enroll（）函数连接到合同时，我收到了一个

错误：无效地址

，我现在已经用多种方式重新编写了代码，并且不管发生什么，总是收到相同的错误

在这里查看了很多帖子后，我了解到这样做时一个相当常见的问题是我需要设置“默认值”——这是我在componentDidMount函数中第一次连接到web3时以及通过contract.defaults函数连接到contract时都做过的。到目前为止，这也没有造成什么不同

任何关于我在这里做错了什么的想法都将不胜感激

相关版本如下

“web3”：“^1.2.1”， “网页包”：“^4.20.2”， “反应”：“^16.2.0”

“块菌合同”：“^3.0.4”， “solc”：“0.4.18”

下面是尝试连接到合同的页面

    componentDidMount = () => {
    if(this.state.web3MetaON == false && this.state.accUnlock == false) {

      if (typeof web3 != 'undefined') {

        this.web3Provider = web3.currentProvider
        web3 = new Web3(web3.currentProvider)
        this.setState({web3MetaON: true})
        const accountID = web3.eth.accounts[0];
        web3.eth.defaultAccount = accountID;
        console.log('Window opening in older browser') 

        // check if accountID is available
        if(accountID !== null || accountID !== undefined) {
        this.setState({accUnlock: true})
        this.setState({account: accountID})

        this.loadDataContract(accountID)

    }
    else {
        console.log('Error on accessing account')
          this.setState({accUnlock: false})
    }
  }
    else {
          window.alert("Please connect to Metamask.")
          this.setState({web3MetaON: false})
          // ::TO-DO method to invoke retry after 2 seconds
        }
      }

      // Below loads web3 and sets state if browser
      // is and a modern ethereum browser 
      else if (window.ethereum && this.state.web3MetaON == false && this.state.accUnlock == false) {
        window.web3 = new Web3(ethereum)
        try {
          // Request account access if needed
          const accountID = ethereum.enable()
          web3.eth.sendTransaction({/* ... */})
          // setting state to accountID
          this.setState({account: accountID})
          this.setState({accUnlock: true})

          console.log('Window opening in modern browser')

        } catch (error) {
          console.log(error, 'Modern Browser failed')
          this.setState({web3MetaON: false})
        }
        console.log('Non-Ethereum browser detected. You should consider trying MetaMask!')
      }
    };

  loadDataContract = () =>  {
      const contract = TruffleContract(DataAccess)
      contract.setProvider(this.web3Provider)
      contract.defaults({from: this.web3Provider});

      // deploy contract
      contract.deployed().then((DataAccessInstance) => {
              this.DataAccessInstance = DataAccessInstance;
              DataAccessInstance.enroll()
                }).then(data => {
                window.alert("contract loaded.", data)

              }).catch(err => console.log("data load data this is ", err))
            };

contract DataAccess {

    // This declares a new complex type which
    // will be used for variables
    // it represents a single usersData
    struct DataLocation {
        string ownerName;
        string ownerID;
        string url;
        string dateOfAccess;
        string timeOfAccess;
        uint accessCount;
        uint index;
    }

    struct Index {
        uint indexLocation;
    }

    // store Data that has a location
    mapping(address => DataLocation) private datastores;

    mapping (address => uint) private balances;

    // store datalocation Count
    uint public datalocationsCount;

    // userIndex stors location of pointers
    address[] public userIndex;

    // stored event
    event storedEvent (
        uint indexed _dataLocationId
    );

    // event for new data location 
    event LogNewData   (
        address indexed dataAddress, 
        string ownerName,
        string url,
        string ownerID,
        string dateOfAccess,
        string timeOfAccess,
       // uint accessCount,
        uint index);


    // event for new updated data  location 
    event LogUpdateData   (
        address indexed dataAddress,
        string ownerName,
        string url,
        string ownerID,
        string dateOfAccess,
        string timeOfAccess,
     //   uint accessCount,
        uint index);

    function enroll() public returns (uint){
      /* Set the sender's balance to 1000, return the sender's balance */
        address user = msg.sender;

        balances[user] = 1000; 
        return user.balance;
    }

下面是solidity合同的一部分

    componentDidMount = () => {
    if(this.state.web3MetaON == false && this.state.accUnlock == false) {

      if (typeof web3 != 'undefined') {

        this.web3Provider = web3.currentProvider
        web3 = new Web3(web3.currentProvider)
        this.setState({web3MetaON: true})
        const accountID = web3.eth.accounts[0];
        web3.eth.defaultAccount = accountID;
        console.log('Window opening in older browser') 

        // check if accountID is available
        if(accountID !== null || accountID !== undefined) {
        this.setState({accUnlock: true})
        this.setState({account: accountID})

        this.loadDataContract(accountID)

    }
    else {
        console.log('Error on accessing account')
          this.setState({accUnlock: false})
    }
  }
    else {
          window.alert("Please connect to Metamask.")
          this.setState({web3MetaON: false})
          // ::TO-DO method to invoke retry after 2 seconds
        }
      }

      // Below loads web3 and sets state if browser
      // is and a modern ethereum browser 
      else if (window.ethereum && this.state.web3MetaON == false && this.state.accUnlock == false) {
        window.web3 = new Web3(ethereum)
        try {
          // Request account access if needed
          const accountID = ethereum.enable()
          web3.eth.sendTransaction({/* ... */})
          // setting state to accountID
          this.setState({account: accountID})
          this.setState({accUnlock: true})

          console.log('Window opening in modern browser')

        } catch (error) {
          console.log(error, 'Modern Browser failed')
          this.setState({web3MetaON: false})
        }
        console.log('Non-Ethereum browser detected. You should consider trying MetaMask!')
      }
    };

  loadDataContract = () =>  {
      const contract = TruffleContract(DataAccess)
      contract.setProvider(this.web3Provider)
      contract.defaults({from: this.web3Provider});

      // deploy contract
      contract.deployed().then((DataAccessInstance) => {
              this.DataAccessInstance = DataAccessInstance;
              DataAccessInstance.enroll()
                }).then(data => {
                window.alert("contract loaded.", data)

              }).catch(err => console.log("data load data this is ", err))
            };

contract DataAccess {

    // This declares a new complex type which
    // will be used for variables
    // it represents a single usersData
    struct DataLocation {
        string ownerName;
        string ownerID;
        string url;
        string dateOfAccess;
        string timeOfAccess;
        uint accessCount;
        uint index;
    }

    struct Index {
        uint indexLocation;
    }

    // store Data that has a location
    mapping(address => DataLocation) private datastores;

    mapping (address => uint) private balances;

    // store datalocation Count
    uint public datalocationsCount;

    // userIndex stors location of pointers
    address[] public userIndex;

    // stored event
    event storedEvent (
        uint indexed _dataLocationId
    );

    // event for new data location 
    event LogNewData   (
        address indexed dataAddress, 
        string ownerName,
        string url,
        string ownerID,
        string dateOfAccess,
        string timeOfAccess,
       // uint accessCount,
        uint index);


    // event for new updated data  location 
    event LogUpdateData   (
        address indexed dataAddress,
        string ownerName,
        string url,
        string ownerID,
        string dateOfAccess,
        string timeOfAccess,
     //   uint accessCount,
        uint index);

    function enroll() public returns (uint){
      /* Set the sender's balance to 1000, return the sender's balance */
        address user = msg.sender;

        balances[user] = 1000; 
        return user.balance;
    }

当试图根据反馈重写合同时，结果仍然是地址无效的错误

  loadDataContract = () =>  {

      const contract = TruffleContract(DataAccess)
      contract.setProvider(this.web3Provider)
      contract.defaults({from: this.web3Provider});


      // initial function
      contract.at('0x8a4A12479486A427109e964e90CaEB5798C13A01').enroll().then((Output) => {
        this.setState({value: Output})
      }).catch(err => console.log("Enroll function error ", err))

    };

---

您应该使用

contract.new（）

部署新合约。如果要使用已部署的协定，请使用

contract.at（）

---

contract.deployed（）

例如用于测试，当您运行

truffle test

命令时，它返回在迁移脚本中部署的契约。

您应该使用

contract.new（）

部署新契约。如果要使用已部署的协定，请使用

contract.at（）

---

contract.deployed（）

例如用于测试，当您运行

truffle test

命令时，它返回在迁移脚本中部署的契约。

谢谢@igor Sobolev。在重写代码时，我仍然无法访问合同，并且出现了相同的错误。让我们看看问题的更新代码片段。如果您对

合同中的
参数有任何其他想法，我们将不胜感激。默认值
应该是发送交易的地址（web3Provider是否返回地址？）。此外，您可以尝试在
中重写函数调用。然后（）
如下：
合同（'0x8A4A1247948A427109E964E90CAEB5798C13A01'）。然后（（实例）=>return instance.enroll（））。然后（（输出）=>…
非常感谢您的建议！我现在得到了要加载的合同，但不得不使用这个.web3Provider.selectedAddress
合同。默认值（{from:this.web3Provider.selectedAddress}）
这就是我阅读的文档似乎没有使用的用户地址传递给合同的方式吗？您对如何连接到合同而不写
合同有什么建议吗？地址（'0x8a4A12479486A427109e964e90CaEB5798C13A01'）
并传递一个变量而不是合同ID？再次感谢IgorThanks@igor Sobolev。在重写代码时，我仍然无法访问合同，并且出现了相同的错误。让我们看看问题的更新代码片段。对于
合同中的
参数的任何其他想法，我们将不胜感激。默认值
>应该是从中发送事务的地址（web3Provider是否返回地址？）=>…
非常感谢您的建议！我现在获得了要加载的合同，但必须使用this.web3Provider.selectedAddress
contract.defaults（{from:this.web3Provider.selectedAddress}）
这就是我阅读的文档似乎没有使用的用户地址传递给合同的方式吗？您对如何连接到合同而不写
合同有什么建议吗？地址（'0x8a4A12479486A427109e964e90CaEB5798C13A01'）
并传递一个变量而不是合同ID？再次感谢Igor