以太坊研究系列【geth客户端调用mist部署的智能合约】

以太坊研究系列【geth客户端调用mist部署的智能合约】 | Ecency

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在Mist钱包中部署以下合约：

pragma solidity ^0.4.11;

contract MetaCoin {  
    mapping (address => uint) balances;  
  
    event Transfer(address indexed _from, address indexed _to, uint256 _value);  
  
    function MetaCoin() public {  
        balances[tx.origin] = 10000;  
    }  
  
    function sendCoin(address receiver, uint amount) public returns(bool sufficient) {  
        if (balances[msg.sender] < amount) return false;  
        balances[msg.sender] -= amount;  
        balances[receiver] += amount;  
        Transfer(msg.sender, receiver, amount);  
        return true;  
    }  
}

在geth客户端定义智能合约的interface，这个可以在Mist的“显示界面”找到，如下：

title

在geth客户端将这个json复制并赋值到abiMetaCoin
> var abiMetaCoin = [ { "constant": false, "inputs": [ { "name": "receiver", "type": "address" }, { "name": "amount", "type": "uint256" } ], "name": "sendCoin", "outputs": [ { "name": "sufficient", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "inputs": [], "payable": false, "stateMutability": "nonpayable", "type": "constructor" }, { "anonymous": false, "inputs": [ { "indexed": true, "name": "_from", "type": "address" }, { "indexed": true, "name": "_to", "type": "address" }, { "indexed": false, "name": "_value", "type": "uint256" } ], "name": "Transfer", "type": "event" } ];
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获取智能合约地址，也是在Mist界面的“复制地址”得到，并赋值到addrMetaCoin，如下：

var addrMetaCoin = "0xAC13705322CB7C7b35544C2EE94fad0250C0e04D";
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取得智能合约实例，通过abi和合约地址取得智能合约实例：

var metacoin = web3.eth.contract(abiMetaCoin).at(addrMetaCoin);
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取到实例后，就通过call或者sendTransaction调用接口，更多参见【智能合约】篇

metacoin.sendCoin.sendTransaction(acc1, web3.toWei(1), {from:acc0});
"0x7bd501b9cd9690c03a31977372b5aa7b36f73342e4c44ee893a35f8af6fada91"
合约事件
// 获取事件对象
var myEvent = metacoin.Transfer();
// 监听事件，监听到事件后会执行回调函数
myEvent.watch(function(err, result) {
if (!err) {
console.log(result);
} else {
console.log(err);
}
myEvent.stopWatching();
});