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Function Signature

Future<PortalSwapResult> swap({
  required String swapsApiKey,
  required String chainId,
  required String buyToken,
  required String sellToken,
  required String amount,
})

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Description

Execute a token swap on supported chains. This method handles the entire swap process including finding the best route and executing the transaction.

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Parameters

ParameterTypeRequiredDescription
swapsApiKeyStringYesYour swaps API key
chainIdStringYesThe chain ID in CAIP-2 format
buyTokenStringYesToken address to buy
sellTokenStringYesToken address to sell
amountStringYesAmount to sell (in smallest unit)

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Returns

PortalSwapResult - An object containing:
PropertyTypeDescription
successboolWhether the swap was successful
transactionHashString?The transaction hash

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Example

import 'package:portal_flutter/portal_flutter.dart';

final portal = Portal();

final result = await portal.swap(
  swapsApiKey: 'YOUR_SWAPS_API_KEY',
  chainId: 'eip155:8453', // Base
  sellToken: '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE', // ETH
  buyToken: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913', // USDC
  amount: '1000000000000000', // 0.001 ETH in wei
);

if (result.success) {
  print('Swap successful: ${result.transactionHash}');
}

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Native Token Address

Use the following address for native tokens (ETH, MATIC, etc.): 
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE

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Errors

CodeDescription
NOT_INITIALIZEDPortal was not initialized
SWAP_FAILEDThe swap operation failed
INSUFFICIENT_BALANCENot enough tokens to swap
INVALID_API_KEYThe swaps API key is invalid