Payable functions in Blockchain / Solidity - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to make the function accept Ether payments.

Blockchain / Solidity

function deposit() public [1] {
    // Function body
}

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Apure

Bexternal

Cview

Dpayable

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'view' or 'pure' which do not allow Ether transfers.

Forgetting to add 'payable' causes the function to reject Ether.

The payable keyword allows the function to receive Ether.

2fill in blank

medium

Complete the code to access the amount of Ether sent to the function.

Blockchain / Solidity

function deposit() public payable {
    uint amount = [1];
}

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Amsg.value

Bmsg.sender

Caddress(this).balance

Dtx.gasprice

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'msg.sender' which is the sender's address, not the amount.

Using 'address(this).balance' which is the contract's total balance, not the sent amount.

msg.value holds the amount of Ether (in wei) sent with the transaction.

3fill in blank

hard

Fix the error in the function declaration to allow receiving Ether.

Blockchain / Solidity

function receiveFunds() public [1] {
    // Accept Ether
}

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Apure

Bview

Cpayable

Dinternal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'view' or 'pure' which prevent Ether transfers.

Omitting 'payable' causes the function to reject Ether.

Only functions marked payable can receive Ether.

4fill in blank

hard

Fill both blanks to create a payable fallback function that accepts Ether.

Blockchain / Solidity

fallback() [1] [2] {
    // fallback logic
}

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Apayable

Bview

Cpure

Dexternal

Attempts:

3 left

💡 Hint

Common Mistakes

Marking fallback as 'view' or 'pure' which is invalid.

Omitting 'payable' causes fallback to reject Ether.

The fallback function must be external and payable to accept Ether.

5fill in blank

hard

Fill all three blanks to create a payable receive function that accepts Ether and updates balance.

Blockchain / Solidity

mapping(address => uint) public balances;

receive() external [1] {
    balances[msg.sender] [2]= [3];
}

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Apayable

B+

Cmsg.value

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting 'payable' on the receive function.

Using '=' instead of '+=' which overwrites balance.

Using 'msg.sender' instead of 'msg.value' for amount.

The receive function must be marked payable to accept Ether. The balance is updated by adding (+=) the amount sent (msg.value).