Solidity Smart Contracts: Sending BNB on Ethereum and Deploying on Binance Smart Chain

Solidity is a widely-used programming language for developing smart contracts on the Ethereum network. These self-executing contracts are immutable and ideal for financial transactions. This guide will walk you through creating a Solidity smart contract to send BNB coins on Ethereum, charge gas fees, and deploy it on the Binance Smart Chain.

Developing a Solidity Smart Contract for Sending BNB

Step 1: Import ERC-20 Interface

To manage BNB tokens, import the ERC-20 standard interface and define the contract structure:

pragma solidity ^0.8.0;

interface IERC20 {
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
}

contract BNBSender {
    address public sender;
    address public recipient;
    uint256 public amount;

    constructor(address _recipient, uint256 _amount) {
        sender = msg.sender;
        recipient = _recipient;
        amount = _amount;
    }

    function send() external returns (bool) {
        IERC20 BNB = IERC20(0xB8c77482e45F1F44dE1745F52C74426C631bDD52);
        BNB.transferFrom(sender, recipient, amount);
        return true;
    }
}

Key Components:

• State Variables: sender, recipient, and amount store transaction details.
• send() Function: Transfers BNB using the ERC-20 transferFrom method.

Charging Gas Fees on Ethereum

Gas fees incentivize miners to process transactions. Modify the contract to include a gas fee mechanism:

modifier paysGasFee() {
    IERC20 BNB = IERC20(0xB8c77482e45F1F44dE1745F52C74426C631bDD52);
    uint256 gasPrice = tx.gasprice;
    uint256 gasUsed = tx.gasprice * 21000;
    uint256 gasCost = gasPrice * gasUsed;
    require(BNB.transferFrom(msg.sender, address(this), gasCost), "Gas fee payment failed");
    _;
}

function send() external paysGasFee returns (bool) {
    IERC20 BNB = IERC20(0xB8c77482e45F1F44dE1745F52C74426C631bDD52);
    BNB.transferFrom(sender, recipient, amount);
    return true;
}

How It Works:

1. Calculates gas cost based on current gasPrice.
2. Requires the sender to pay the fee before executing the transaction.

Deploying on Binance Smart Chain (BSC)

Step 1: Configure MetaMask

• Switch your MetaMask network to Binance Smart Chain (Mainnet or Testnet).

Step 2: Compile and Deploy

1. Use Remix IDE to compile the contract.
2. Select the BSC network in Remix.
3. Click Deploy and confirm the transaction.

👉 Learn how to configure MetaMask for BSC

Interacting with the Contract:

• Enter the recipient’s address and BNB amount in the send function.
• Pay gas fees in BNB to complete the transaction.

Why Use Binance Smart Chain?

• Lower Fees: BSC transactions cost significantly less than Ethereum.
• Faster Transactions: BSC’s consensus mechanism enables quicker confirmations.
• EVM Compatibility: Easily port Ethereum contracts to BSC.

👉 Compare Ethereum vs. BSC gas fees

FAQ

1. Can I use the same contract for Ethereum and BSC?

Yes, but ensure the BNB token address matches the network (Ethereum: 0xB8c..., BSC: 0xbb4...).

2. How do I calculate gas fees accurately?

Use tools like BscScan’s gas tracker or estimate fees dynamically in your contract.

3. What if the gas fee payment fails?

The transaction reverts, and no BNB is transferred.

4. Is BSC more secure than Ethereum?

Ethereum has a longer track record, but BSC offers robust security for most use cases.

Conclusion

Developing Solidity smart contracts for cross-chain BNB transfers involves:

1. Structuring the contract with ERC-20 standards.
2. Implementing gas fee logic.
3. Deploying on BSC for cost efficiency.

By mastering these steps, you can build secure, decentralized applications leveraging both Ethereum and Binance Smart Chain.