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@karthickpdy karthickpdy/app.js
Created Sep 1, 2017

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What would you like to do?
Interacting with smart contracts
// Import the page's CSS. Webpack will know what to do with it.
import "../stylesheets/app.css";
// Import libraries we need.
import { default as Web3} from 'web3';
import { default as contract } from 'truffle-contract'
// Import our contract artifacts and turn them into usable abstractions.
import stock_exchange_artifacts from '../../build/contracts/StockExchange.json'
var StockExchange = contract(stock_exchange_artifacts);
// The following code is simple to show off interacting with your contracts.
// As your needs grow you will likely need to change its form and structure.
// For application bootstrapping, check out window.addEventListener below.
var accounts;
var account;
window.App = {
start: function() {
var self = this;
// Bootstrap the StockExchange abstraction for Use.
StockExchange.setProvider(web3.currentProvider);
// Get the initial account balance so it can be displayed.
web3.eth.getAccounts(function(err, accs) {
if (err != null) {
alert("There was an error fetching your accounts.");
return;
}
if (accs.length == 0) {
alert("Couldn't get any accounts! Make sure your Ethereum client is configured correctly.");
return;
}
accounts = accs;
account = accounts[0];
self.refreshBalance();
self.listenEvents();
});
},
listenEvents: function(){
var self = this;
StockExchange.deployed().then(function(instance) {
instance.Transaction({user: account},{fromBlock: "latest", toBlock: 'latest'}).watch(function(err,result){
self.setStatus(result.args._type+" - "+ result.args.user);
});
});
},
setStatus: function(message) {
var status = document.getElementById("status");
status.innerHTML = message;
},
refreshBalance: function() {
var self = this;
var meta;
StockExchange.deployed().then(function(instance) {
meta = instance;
return meta.getBalance.call(account, {from: account});
}).then(function(value) {
var balance_element = document.getElementById("balance");
balance_element.innerHTML = value.valueOf();
return meta.getHoldings.call({from:account});
}).then(function(value){
var balance_element = document.getElementById("holdingBalance");
balance_element.innerHTML = value.valueOf();
}).catch(function(e) {
console.log(e);
self.setStatus("Error getting balance; see log.");
});
web3.eth.getBalance(account,function(error,etherBalance) {
var balance_element = document.getElementById("etherBalance");
balance_element.innerHTML = web3.fromWei(etherBalance,"ether").toNumber();
})
},
buy: function() {
var self = this;
var meta;
StockExchange.deployed().then(function(instance) {
meta = instance;
return meta.buy({from: account,value: web3.toWei(1, "ether")});
}).then(function() {
self.refreshBalance();
}).catch(function(e) {
console.log(e);
self.setStatus("Error sending coin; see log.");
});
},
sell: function() {
var self = this;
var meta;
StockExchange.deployed().then(function(instance) {
meta = instance;
return meta.sell({from: account});
}).then(function() {
self.refreshBalance();
}).catch(function(e) {
console.log(e);
self.setStatus("Error sending coin; see log.");
});
}
};
window.addEventListener('load', function() {
// Checking if Web3 has been injected by the browser (Mist/MetaMask)
if (typeof web3 !== 'undefined') {
// Use Mist/MetaMask's provider
window.web3 = new Web3(web3.currentProvider);
} else {
// fallback - use your fallback strategy (local node / hosted node + in-dapp id mgmt / fail)
window.web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}
App.start();
});
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