makeICOsite.js

var MAINET_RPC_URL = 'https://mainnet.infura.io/metamask' ;
var ROPSTEN_RPC_URL = 'https://ropsten.infura.io/metamask' ;
var KOVAN_RPC_URL = 'https://kovan.infura.io/metamask' ;
var RINKEBY_RPC_URL = 'https://rinkeby.infura.io/metamask' ;

var CURRENT_URL = MAINET_RPC_URL ;

$( document ).ready(function() {
    web3 = new Web3(new Web3.providers.HttpProvider(CURRENT_URL));

    var wallet = '0x45e044ED9Bf130EafafA8095115Eda69FC3b0D20' ;

    $('.check_balance').click(function(){
        address = wallet ;
        balance = getBalance(address) ;
        console.log(balance) ;
    });

    function getBalance(address) {
        if (address.length <= 3) {
            alert("Wallet address is incorrect") ;
            return 0 ;
        }

        web3.eth.getBalance(address, function(error, result){
            console.log('yes') ;
            if(!error) {
                balance = result.toString(10) ;
                setBalance(balance) ;
                $.cookie("address", address);
            } else {
                alert('Some error happens. Please, try again.') ;
                console.error(error);
            }
        });
    }

    function setBalance(wei) {
        eth = wei / 1000000000000000000 ;
        eth = web3.fromWei(wei, 'ether') ;
        $('.balance_positive').html(eth) ;
    }
});