Go-Ethereum

使用 web3 將 ERC20 代幣從一個賬戶轉移到另一個賬戶

  • January 9, 2018

我有兩個正在管理的乙太坊生成帳戶,需要以程式方式在兩個帳戶之間發送令牌。

我創建了兩個帳戶,可以將 ERC20 代幣從合約發送到地址,但需要從地址發送到地址。我正在使用乙太坊網站上的範例 Solidity 令牌。

它有一個名為 transfer 的功能,用於在賬戶之間發送代幣:

function transfer(address _to, uint256 _value)

我現在需要使用 web3 連接到這個合約,然後將生成的一定數量的令牌發送到另一個帳戶。我一直在努力解決如何做到這一點,並希望這個社區可以提供幫助。這是我到目前為止使用的 web3 版本 0.20.0:

const Web3 = require("web3");
const web3 = new Web3();
web3.setProvider(new 
web3.providers.HttpProvider("https://ropsten.infura.io/XXXXXX"));
var abi = [ {} ] // redacted on purpose
const account1 = "0x9..."
const account2 = "0x3..."
var count = web3.eth.getTransactionCount(account1);
var abiArray = abi;
var contractAddress = "0x2...";
var contract =  web3.eth.contract(abiArray).at(contractAddress);


var data = contract.transfer.getData(account2, 10000, {from: account1});
var gasPrice = web3.eth.gasPrice;
var gasLimit = 90000;

var rawTransaction = {
 "from": account1,
 "nonce": web3.toHex(count),
 "gasPrice": web3.toHex(gasPrice),
 "gasLimit": web3.toHex(gasLimit),
 "to": account2,
 "value": 0,
 "data": data,
 "chainId": 0x03
};

var privKey = new Buffer('XXXXXXXXXXXXXX', 'hex');
var tx = new Tx(rawTransaction);

tx.sign(privKey);
var serializedTx = tx.serialize();

web3.eth.sendRawTransaction('0x' + serializedTx.toString('hex'), function(err, hash) {
 if (!err)
     console.log(hash);
 else
     console.log(err);
});

但是,此程式碼不會從一個帳戶轉移到另一個帳戶。

代幣合約程式碼:

contract Token {
   // Public variables of the token
   string public name;
   string public symbol;
   uint8 public decimals = 18;
   // 18 decimals is the strongly suggested default, avoid changing it
   uint256 public totalSupply;

   // This creates an array with all balances
   mapping (address => uint256) public balanceOf;
   mapping (address => mapping (address => uint256)) public allowance;

   // This generates a public event on the blockchain that will notify clients
   event Transfer(address indexed from, address indexed to, uint256 value);

   // This notifies clients about the amount burnt
   event Burn(address indexed from, uint256 value);

   /**
    * Constrctor function
    *
    * Initializes contract with initial supply tokens to the creator of the contract
    */
   function Token(
       uint256 initialSupply,
       string tokenName,
       string tokenSymbol
   ) public {
       totalSupply = initialSupply * 10 ** uint256(decimals);  // Update total supply with the decimal amount
       balanceOf[msg.sender] = totalSupply;                // Give the creator all initial tokens
       name = tokenName;                                   // Set the name for display purposes
       symbol = tokenSymbol;                               // Set the symbol for display purposes
   }

   /**
    * Internal transfer, only can be called by this contract
    */
   function _transfer(address _from, address _to, uint _value) internal {
       // Prevent transfer to 0x0 address. Use burn() instead
       require(_to != 0x0);
       // Check if the sender has enough
       require(balanceOf[_from] >= _value);
       // Check for overflows
       require(balanceOf[_to] + _value > balanceOf[_to]);
       // Save this for an assertion in the future
       uint previousBalances = balanceOf[_from] + balanceOf[_to];
       // Subtract from the sender
       balanceOf[_from] -= _value;
       // Add the same to the recipient
       balanceOf[_to] += _value;
       Transfer(_from, _to, _value);
       // Asserts are used to use static analysis to find bugs in your code. They should never fail
       assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
   }

   /**
    * Transfer tokens
    *
    * Send `_value` tokens to `_to` from your account
    *
    * @param _to The address of the recipient
    * @param _value the amount to send
    */
   function transfer(address _to, uint256 _value) public {
       _transfer(msg.sender, _to, _value);
   }

   /**
    * Transfer tokens from other address
    *
    * Send `_value` tokens to `_to` in behalf of `_from`
    *
    * @param _from The address of the sender
    * @param _to The address of the recipient
    * @param _value the amount to send
    */
   function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
       require(_value <= allowance[_from][msg.sender]);     // Check allowance
       allowance[_from][msg.sender] -= _value;
       _transfer(_from, _to, _value);
       return true;
   }

   /**
    * Set allowance for other address
    *
    * Allows `_spender` to spend no more than `_value` tokens in your behalf
    *
    * @param _spender The address authorized to spend
    * @param _value the max amount they can spend
    */
   function approve(address _spender, uint256 _value) public
       returns (bool success) {
       allowance[msg.sender][_spender] = _value;
       return true;
   }

   /**
    * Set allowance for other address and notify
    *
    * Allows `_spender` to spend no more than `_value` tokens in your behalf, and then ping the contract about it
    *
    * @param _spender The address authorized to spend
    * @param _value the max amount they can spend
    * @param _extraData some extra information to send to the approved contract
    */
   function approveAndCall(address _spender, uint256 _value, bytes _extraData)
       public
       returns (bool success) {
       tokenRecipient spender = tokenRecipient(_spender);
       if (approve(_spender, _value)) {
           spender.receiveApproval(msg.sender, _value, this, _extraData);
           return true;
       }
   }

   /**
    * Destroy tokens
    *
    * Remove `_value` tokens from the system irreversibly
    *
    * @param _value the amount of money to burn
    */
   function burn(uint256 _value) public returns (bool success) {
       require(balanceOf[msg.sender] >= _value);   // Check if the sender has enough
       balanceOf[msg.sender] -= _value;            // Subtract from the sender
       totalSupply -= _value;                      // Updates totalSupply
       Burn(msg.sender, _value);
       return true;
   }

   /**
    * Destroy tokens from other ccount
    *
    * Remove `_value` tokens from the system irreversibly on behalf of `_from`.
    *
    * @param _from the address of the sender
    * @param _value the amount of money to burn
    */
   function burnFrom(address _from, uint256 _value) public returns (bool success) {
       require(balanceOf[_from] >= _value);                // Check if the targeted balance is enough
       require(_value <= allowance[_from][msg.sender]);    // Check allowance
       balanceOf[_from] -= _value;                         // Subtract from the targeted balance
       allowance[_from][msg.sender] -= _value;             // Subtract from the sender's allowance
       totalSupply -= _value;                              // Update totalSupply
       Burn(_from, _value);
       return true;
   }
}

您不能將令牌直接從一個地址發送到另一個地址。代幣餘額僅存在於代幣合約儲存中。你必須向合約發送一筆交易,表明你想要進行轉賬,因此合約可以相應地更新余額。

我在 geth 控制台中給出了這個例子

   var theContract=eth.contract(THE_CONTRACT_ABI)
   var contractInstance = theContract.at(THE_CONTRACT_ADDRESS)
   personal.unlockAccount(YOUR_ACCOUNT_ADDRESS,YOUR_PASSWORD,100000)
   contractInstance.transfer(TO_THIS_ADDRESS,web3.toWei(20000),{from:YOUR_ACCOUNT_ADDRESS})

引用自:https://ethereum.stackexchange.com/questions/29587