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This article mainly explains "how to use Solidity Zombies". Friends who are interested might as well take a look. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn how to use Solidity Zombies.

ZombieFactory.sol

Pragma solidity ^ 0.4.19 × import ". / ownable.sol"; contract ZombieFactory is Ownable {event NewZombie (uint zombieId, string name, uint dna); uint dnaDigits = 16; uint dnaModulus = 10 * * dnaDigits; uint cooldownTime = 1 days; struct Zombie {string name; uint dna; uint32 level; uint32 readyTime;} Zombie [] public zombies; mapping (uint = > address) public zombieToOwner; mapping (address = > uint) ownerZombieCount Function _ createZombie (string _ name, uint _ dna) internal {uint id = zombies.push (Zombie (_ name, _ dna, 1, uint32 (now + cooldownTime))-1; zombieToOwner [id] = msg.sender; ownerZombieCount [msg.sender] + +; NewZombie (id, _ name, _ dna);} function _ generateRandomDna (string _ str) private view returns (uint) {uint rand = uint (keccak256 (_ str)) Return rand% dnaModulus;} function createRandomZombie (string _ name) public {require (ownerZombieCount [msg.sender] = 0); uint randDna = _ generateRandomDna (_ name); randDna = randDna-randDna% 100; _ createZombie (_ name, randDna);}}

Ownable is an Ownable contract from the OpenZeppelin Solidity library. Events are a mechanism for communication between contracts and blockchain. Your front-end application "listens" to certain events and reacts. Such as:

Var abi = / / abi is generated by the compiler var ZombieFactoryContract = web3.eth.contract (abi) var contractAddress = / contract address var ZombieFactory = ZombieFactoryContract.at (contractAddress) / / ZombieFactory generated on Ethernet Square after release can access public functions and events / / listen for NewZombie events, and update UI var event = ZombieFactory.NewZombie (function (error, result) {if (error) return generateZombie (result.zombieId, result.name, result.dna)})

ZombieFeeding.sol

Pragma solidity ^ 0.4.19 X import ". / zombiefactory.sol"; contract KittyInterface {function getKitty (uint256 _ id) external view returns (bool isGestating, bool isReady, uint256 cooldownIndex, uint256 nextActionAt, uint256 siringWithId, uint256 birthTime, uint256 matronId, uint256 sireId, uint256 generation, uint256 genes);} contract ZombieFeeding is ZombieFactory {KittyInterface kittyContract; modifier ownerOf (uint _ zombieId) {require (msg.sender = zombieToOwner [_ zombieId]) _;} function setKittyContractAddress (address _ address) external onlyOwner {kittyContract = KittyInterface (_ address);} function _ triggerCooldown (Zombie storage _ zombie) internal {_ zombie.readyTime = uint32 (now + cooldownTime);} function _ isReady (Zombie storage _ zombie) internal view returns (bool) {return (_ zombie.readyTime = _ level); _;} function withdraw () external onlyOwner {owner.transfer (this.balance) } function setLevelUpFee (uint _ fee) external onlyOwner {levelUpFee = _ fee;} function levelUp (uint _ zombieId) external payable {require (msg.value = = levelUpFee); zombies [_ zombieId] .level + +;} function changeName (uint _ zombieId, string _ newName) external aboveLevel (2, _ zombieId) ownerOf (_ zombieId) {zombies [_ zombieId]. Name = _ newName } function changeDna (uint _ zombieId, uint _ newDna) external aboveLevel (20, _ zombieId) ownerOf (_ zombieId) {zombies [_ zombieId]. Dna = _ newDna;} function getZombiesByOwner (address _ owner) external view returns (uint []) {uint [] memory result = new uint [] (ownerZombieCount [_ owner]); uint counter = 0; for (uint I = 0; I < zombies.length) If +) {if (zombieToOwner [I] = = _ owner) {result [counter] = I; counter++;}} return result;}}

Msg.value is a way to see how many ethers are sent to the contract, and ether is a built-in unit.

What happens here is that some people will call this function from web3.js (from the front end of DApp), like this:

/ / suppose `OnlineStore` points to your contract on Ethernet Square: OnlineStore.buySomething () .send (from: web3.eth.defaultAccount, value: web3.utils.toWei (0.001))

ZombieBattle.sol

Pragma solidity ^ 0.4.19 × import ". / zombiehelper.sol"; contract ZombieBattle is ZombieHelper {uint randNonce = 0; uint attackVictoryProbability = 70; function randMod (uint _ modulus) internal returns (uint) {randNonce++; return uint (keccak256 (now, msg.sender, randNonce))% _ modulus;} function attack (uint _ zombieId, uint _ targetId) external ownerOf (_ zombieId) {Zombie storage myZombie = zombies [_ zombieId]; Zombie storage enemyZombie = zombies [_ targetId]; uint rand = randMod If (rand

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