A smart contract is a blockchain-based digital agreement that executes itself when two or more parties meet all the conditions or clauses set before processing a transaction. These contracts are significant as they provide immutability, transparency, accuracy, speed and autonomy.
The script for a smart contract in Ethereum is written in Solidity, a programming language, compiled into JSON and deployed to a specific address on the blockchain. So, to create and deploy Ethereum smart contracts, it is essential to know about Solidity. .
Table of Contents
What is Solidity?
How to create an Ethereum Smart Contract?
Step 1: Create a wallet at Metamask
Install the Metamask Chrome extension, enable it first, and then go to the icon located on the top right of the browser page to open it in a new tab.
Select “Create Wallet” and agree to the terms and conditions by pressing the “I agree” button to proceed further. Now, create a password.
Once the password is created, you will get a secret backup phrase for backing up and restoring the account. Keep this phrase confidential as anyone can steal your Ether with this phrase.
Now, make sure you are in the “Main Ethereum Network.” If you can find a checkmark next to “Main Ethereum Network,” you are in the right place.
Step 2: Select any one test network
You can find the following test network options in the “Main Ethereum Network:
- Robsten Test Network
- Kovan Test Network
- Rinkeby Test Network
- Goerli Test Network
Step 3: Add some dummy Ethers
To examine the smart contract, you must have some dummy Ethers in your MetaMask wallet. Select “Deposit” and then the “Get Ether” button from Test Faucet.
Click on “Request one ether from the faucet” to proceed, and you will get 1 ETH. When you get the dummy Ethers, you can start writing smart contracts on the Remix Browser IDE using Solidity.
Step 4: Editor remix to write the smart contract in Solidity
To write our Solidity code, we will use Remix Browser IDE, which provides features including Static analysis, Syntax and error highlighting, and an integrated debugger.
Step 5: Create a .sol extension file
Visit https://remix.ethereum.org and open Remix Browser. Select the plus icon located on the top left side to generate a .sol extension file.
Step 6: A model smart contract code to build ERC20 tokens
ERC20.sol is a standard template to create ERC20 tokens. Follow the below-mentioned codes:
Step 7: Deploy the contract
Deploy the smart contract to the Ethereum test network by clicking on the Deploy button on the Remix window’s right-hand side. When the transaction is successful, the smart contract address will be visible on the right-hand side of the remix window.
If you want to check the tokens in your wallet, click add tokens from the metamask window, enter the smart contract address and press ok. The number of tokens is visible there.
How to test an Ethereum smart contract?
- Try to run all smart contract methods like transfer, total supply, and balance (in the smart contract example mentioned above) present on the right-hand side of the remix window.
- Attempt to transfer some tokens to other Ethereum wallet addresses and then call the balance method to check the balance of that address.
- Run the total supply method and try to get the total supply.
Steps to deploy Ethereum Smart Contracts
- Shift to the main Ethereum network at metamask to make your smart contract live.
- Add real Ethers.
- Deploy your smart contract again using Remix by referring to the earlier steps.
- Once the smart contract is deployed successfully, go to http://www.etherscan.io, search for your smart contract address, and select your smart contract.
- To verify the contract, click on “verify the contract.”
- Copy and paste your smart contract code at Etherscan.
- Change “optimization” to Yes, if you selected optimization at Remix, or select No.
- Select Verify.
- If no trouble occurs, your smart contract will be live.
- You may now run your smart contract methods at Etherscan.
You can smoothly create a Smart Contract on Ethereum using the steps mentioned above.