ERC-1155 multi-token standard in Blockchain / Solidity - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the ERC-1155 contract inheritance.

Blockchain / Solidity

contract MyToken is [1] {
    // contract code
}

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AERC20

BERC1155

CERC721

DOwnable

Attempts:

3 left

💡 Hint

Common Mistakes

Using ERC20 or ERC721 inheritance instead of ERC1155.

Forgetting to inherit any contract.

The ERC-1155 standard contract inherits from ERC1155 in Solidity.

2fill in blank

medium

Complete the code to mint a new token with a specific ID and amount.

Blockchain / Solidity

function mintToken(address to, uint256 id, uint256 amount) public {
    _mint(to, id, [1], "");
}

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Aid

Bmsg.sender

Camount

Dto

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the recipient address instead of amount.

Passing the token ID instead of amount.

The _mint function requires the amount of tokens to mint as the third argument.

3fill in blank

hard

Fix the error in the transfer function call by completing the missing argument.

Blockchain / Solidity

safeTransferFrom(msg.sender, to, id, amount, [1]);

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A""

Baddress(0)

C0x0

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using null or zero address instead of empty bytes.

Omitting the last parameter.

The last argument is a bytes data parameter, usually an empty string "" when no data is sent.

4fill in blank

hard

Fill both blanks to create a mapping for balances of token IDs per address.

Blockchain / Solidity

mapping(address => mapping(uint256 => [1])) private [2];

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Auint256

Baddress

Cbalances

Dbool

Attempts:

3 left

💡 Hint

Common Mistakes

Using address or bool as the value type.

Incorrect variable name.

The balances mapping stores the amount (uint256) of each token ID per address.

5fill in blank

hard

Fill all three blanks to implement a function that returns the URI for a given token ID.

Blockchain / Solidity

function uri(uint256 [1]) public view override returns (string memory) {
    return string(abi.encodePacked([2], Strings.[3]([1]), ".json"));
}

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AtokenId

BbaseURI

CtoString

Did

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong parameter names.

Forgetting to convert the token ID to string.

The function takes tokenId, concatenates baseURI with the string version of tokenId using toString, and adds the .json extension.