Fuels-ts

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Managing Deployed Contracts ​

To interact with a deployed contract using the SDK without redeploying it, you only need the contract ID and its JSON ABI. This allows you to bypass the deployment setup.

Contract ID ​

The contractId property from the Contract class is of type AbstractAddress, an abstract class that is exclusively extended by the Address class.

The Address class wraps all methods from the AbstractAddress class and adds a single property: bech32Address. This property is a string encoded in Bech32 format, recognizable by the human-readable prefix fuel followed by the separator 1.

When you log the contractId property of an instantiated Contract using console.log, the output appears as follows:

console
  Address {
    bech32Address: 'fuel1e5tdjlzufcvwut5dvs5yglweepmrevpnvuvt2djj6pyl3mygkwaq8m7f20'
  }

If you have already an instantiated and deployed contract in hands you can create another contract instance simply by using the contractId property and the contract JSON ABI:

ts
const deployedEchoContract = new Contract(contractId, abi, wallet);

const { value: echoed10 } = await deployedEchoContract.functions
  .echo_u8(10)
  .simulate();
// value 10
See code in context

The previous example assumes that you have a Contract instance at hand. However, some Fuel tools and Sway use the b256 type format, a hex-encoded string-like type, for contract IDs.

You might have this format instead, for example, if you have deployed your contract with forc deploy.

The process of instantiating a Contract remains the same when using a contract ID of type b256:

ts
const contract = new Contract(b256, abi, wallet);

const { value: echoed50 } = await contract.functions.echo_u8(50).simulate();
See code in context