：使用geth發送交易

啟動一個串連到節點的互動控制台，您可以參考文檔開啟geth互動控制台來建立一個互動控制台

建立一個以太坊賬戶，如果您已經在節點上建立了以太坊賬戶，可以使用已有賬戶完成後續操作

// create a account that use empty password
var account = personal.newAccount("");
// using an existing account in node
// var account = eth.accounts[0]
// unlock account for 300 seconds with empty password
personal.unlockAccount(account, "", 300);
// set it as default account
web3.eth.defaultAccount = account;

指定智能合約的地址和ABI，並發起調用。您可以參考部署智能合約中的步驟來部署智能合約，並擷取智能合約的地址和ABI。

// your contract address that you want to call
var address = "0x0000000";
// your contarct ABI that address corresponds to
var abi = [{"constant":true,"inputs":[],"name":"storedData","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"x","type":"uint256"}],"name":"set","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"get","outputs":[{"name":"retVal","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[{"name":"initVal","type":"uint256"}],"payable":false,"type":"constructor"}];
var contract = eth.contract(abi).at(address)
// call get method of demo contract
contract.get()
// call set method of demo contract, and create a new transaction
contract.set(999)