Whitepaper - Ethereum Classic With Cover

Ethereum Classic Documentation, Release 0.1
Editing backend contract file
By default, a new project contains a contract “Contract” for backend development on the blockchain using the
Solidity language and the “index.html” for the frontend. Check the Solidity tutorial for references.
Edit the empty default contract “Contract”, e.g.
contract Rating {
function setRating(bytes32 _key, uint256 _value) {
ratings[_key] = _value;
}
mapping (bytes32 => uint256) public ratings;
}
Check the Solidity tutorial for help getting started with the solidity programming language.
Save changes
Editing frontend html files
Select default index.html file and enter the following code
....
function getRating() {
var param = document.getElementById(“query”).value;
var res = contracts[“Rating”].contract.ratings(param);
document.getElementById(“queryres”).innerText = res;
}
function setRating() {
var key = document.getElementById("key").value;
var value = parseInt(document.getElementById("value").value);
var res = contracts["Rating"].contract.setRating(key, value);
}
Ratings
Store:
Save
Query:
Then it is possible to add many contract files as well as many HTML, JavaScript, css files
Scenarios Editor
Scenarios can be used to test and debug contracts.
A scenario is effectively a local blockchain where blocks can be mined without PoW – otherwise testing would be
quite slow ;).
A scenario consists of a sequence of transactions. Usually, a scenario would start with the contract creation
scenarios of the dapp. In addition, further transactions can be added to test and debug the dapp. Scenarios can be
90 Chapter 1. Contents