Calling Another Contract

The call method allows one contract to interact with another contract by sending calldata to it.

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Method

call(destinationContract: Address, calldata: BytesWriter): BytesReader

• Parameters:

  • destinationContract: The address of the contract you want to call.
  • calldata: The data to send to the destination contract, formatted using BytesWriter.

• Returns:

  • BytesReader: The response from the destination contract, which can be parsed as needed.

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Example Usage

import {
  Address,
  BytesWriter,
  Blockchain,
} from "@btc-vision/btc-runtime/runtime";
import { u256 } from 'as-bignum/assembly';

// Define the destination contract address
let destination: Address = Address.fromString(...);

// Create calldata
let calldata = new BytesWriter(64); // 64 is the length in bytes of the calldata
calldata.writeString("methodName");
calldata.writeU256(u256.from(1234)); // Example of adding additional method parameters

// Execute the call
let response = Blockchain.call(destination, calldata);

// Log the response
Blockchain.log(`Response: ${response}`);

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Best Practices

• The calldata must be formatted correctly to match the expected input of the destination contract.
• Ensure that the destination contract is deployed and the address is valid.
• Always parse the BytesReader response correctly to extract meaningful data.
• Errors during the call may not directly throw exceptions but could result in an empty or unexpected response.