Web3js React – Importing Web3 into a React Application

It sounds confusing and basing on the version of web3 you have the syntax is different. According to the error you got at the first place seems like you are using web3 1.0. However the instance code is for the version 0.2.x.x

Just to clarify, this is how your code will look like in case you're using web3 1.0

import Web3 from 'web3';

const web3 = new Web3(Web3.givenProvider || "http://localhost:8545");
web3.eth.getAccounts().then(console.log);

So basically you create an instance of web3 with the givenProvider (in case you're using metamask or mist) or with the local. Then you get your accounts.

In case you're using the old version of web3 the code is slightly different:

import Web3 from 'web3';

let web3 = null;
if (typeof web3 !== 'undefined') {
  web3 = new Web3(web3.currentProvider);
} else {
  // set the provider you want from Web3.providers
  web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}

web3.eth.getAccounts(callback(error, result){ console.log(result) })

Altough the proper answer to your issue might probbably be to install the module you have referenced, I would strongly recommend you to use the truffle angular boilerplate instead.

It will save you ages worth of nerves, believe me.

EDIT: After thoroughly reading your errors again, I see that it requires "crypto", which is a default package now, breaking old dependencies. Here is a patch.