## Ethereum – Using Ethereumjs-tx and Web3

September 13, 2018

Author: Michael Gord

You must have node and npm downloaded on your computer. After this tutorial you should have sent an ethereum transaction with test-ether on testrpc.

```
npm install web3 ethereumjs-tx ethereumjs-util
```
Download web3, ethereumjs-tx and ethereumjs-util from your terminal.

```
ode
```
Go to your node console.

```
var Web3 = require("web3")
```
Require web3.

```
var web3 = new Web3(new Web3.providers.httpsProvider("https://localhost:8545"))
```
Get web3 Instance in Node Console. 8545 is the default port to connect to.

```
testrpc
```
In a new terminal window run testrpc.

```
web3.eth.getBalance(web3.eth.accounts[0])
```
Check balance of account[0] in Wei.

```
web3.fromWei(web3.eth.getBalance(web3.eth.accounts[0]), 'ether')
```
Check balance of account[0] in Ether.

```
acct1 = web3.eth.accounts[0]

acct2 = web3.eth.accounts[1]

acct3 = web3.eth.accounts[2]
```
Create account helper methods.

```
var balance = (acct) => { return web3.fromWei(web3.eth.getBalance(acct), 'ether').toNumber()}
```
Create balance method.

```
balance(acct1)
```
Query balance of account[0] to make sure its working.

```
web3.eth.sendTransaction({from: acct1, to:acct2, value: web3.toWei(1, 'ether'), gasLimit: 21000, gasPrice: 20000000000})
```
Send 1 test ether from acct1 to acct2.

```
var txHash = _
```
Create variable for txHash output from above.

```
balance(acct2) balance(acct1)
```
Query balance of acct1 and acct1 to make sure the transaction went through.

```
web3.eth.getTransaction(txHash)
```
Check transaction data from txHash.