Does anyone have an example on say Github where they have added additional info? For every transaction recorded on what will be a Private Blockchain, I need to store 3 additional attributes.

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There seems very little examples of actual code where someone has implemented this. After a few days of digging and trial and error, I have come up with a solution that has additional attributes stored on-chain.

In the example, I have added 3 attributes to store specific property data, which would be useful for a Real Estate dApp.

I have forked the contracts from Kaleido's Firefly implementation and amended both ERC20 and ERC721 contracts (kudos goes out to Kaleido). Their original code adds a 'data' field, which I replaced with 3 attributes as follows: -

uint32 propertyNumber uint32 propertyPrice string memory propertyLocation

Of course just adjust them as needed in all places where they are referenced.

See my GitHub repository for the code: -


I hope it helps someone.


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