我需要帮助来建立具有5.0版或更高版本的ERC-721合同

Question

I am trying to write a contract with ERC-721 token system. I have experience with ERC-20, so I thought I can find a tutorial and follow the tutorial. However, tutorials I found are based on solidity version between 4.0~4.2. Nowadays we use 5.0~6.0. Therefore tutorial codes are not working. Is there any tutorial, or code can I look and learn? HELP!

I tried to fix the code, and make suitable for 5.0 or higher, but I failed. Therefore I tried to downgrade solidity and use docker but still get

Error: CompileError: ParsedContract.sol:3:1: ParserError: Source "zeppelin-solidity/contracts/token/ERC721/ERC721Token.sol" not found: Unknown exception in read callback. import 'zeppelin-solidity/contracts/token/ERC721/ERC721Token.sol'; this error. :(

+ I found https://github.com/OpenZeppelin/openzeppelin-solidity , this but I do not know how to write test. Thank you for your time to read this !.

Answer 1

due to renaming, ERC721Token.sol is no longer available in the latest version of OpenZeppelin v2.3.0. change ERC721Token.sol to ERC721.sol , and it should work.

Answer 2

I suggest you have a look at the OpenZeppelin documentation: https://docs.openzeppelin.org/v2.3.0/tokens#erc721

If you have more questions about OpenZeppelin you can always ask in the community forum

I can put together a sample contract in the community forum if you need.