wallet/triggerconstantcontract - Call View Func...

Execute smart contract view/pure functions without creating a blockchain transaction. Perfect for reading contract state, calculating values, or retrieving stored data.

Use CasesCopy Anchor Link

wallet/triggerconstantcontract is essential for:

• Token Balance Queries - Check TRC20 token balances
• Price Feeds - Read oracle price data
• Game State - Query game contract states
• DeFi Positions - Check liquidity pool shares
• Contract Verification - Test function outputs

{
  "contract_address": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t",
  "function_selector": "balanceOf(address)",
  "parameter": "000000000000000000000000a614f803b6fd780986a42c78ec9c7f77e6ded13c",
  "owner_address": "TRX6Q82wMqWNbCCmJPLz9mR8AZwqvUU2pN",
  "visible": true
}

Implementation ExamplesCopy Anchor Link

Common Use CasesCopy Anchor Link

1. Token Balance CheckerCopy Anchor Link

async function checkTokenBalance(tokenAddress, userAddress) {
  const token = new TRC20Contract('API_KEY', tokenAddress);
  
  try {
    const [symbol, decimals, balance] = await Promise.all([
      token.symbol(),
      token.getDecimals(),
      token.balanceOf(userAddress)
    ]);
    
    return {
      token: symbol,
      balance: balance.formatted,
      decimals: decimals,
      hasBalance: BigInt(balance.raw) > 0n
    };
  } catch (error) {
    return {
      error: 'Failed to fetch token data',
      details: error.message
    };
  }
}

2. DEX Price MonitorCopy Anchor Link

async function monitorDexPrice(poolAddress) {
  const getPrice = async () => {
    const result = await callContractView(
      poolAddress,
      'getReserves()'
    );
    
    const reserves = parseReserves(result.constant_result[0]);
    return calculatePrice(reserves.token0, reserves.token1);
  };
  
  return setInterval(async () => {
    const price = await getPrice();
    console.log(`Current price: ${price}`);
  }, 10000); // Check every 10 seconds
}

3. Multi-Call PatternCopy Anchor Link

async function getCompleteTokenInfo(tokenAddress) {
  const functions = [
    'name()',
    'symbol()',
    'decimals()',
    'totalSupply()'
  ];
  
  const results = await Promise.all(
    functions.map(fn => 
      callContractView(tokenAddress, fn)
    )
  );
  
  return {
    name: decodeString(results[0].constant_result[0]),
    symbol: decodeString(results[1].constant_result[0]),
    decimals: decodeUint256(results[2].constant_result[0]),
    totalSupply: decodeUint256(results[3].constant_result[0])
  };
}

Reverted calls still return result.result: trueCopy Anchor Link

result.result reports that the node executed the call. It does not report that the call succeeded. A USDT transfer simulated from an address with no USDT returned this on TRON mainnet on 3 November 2026:

{
  "result": { "result": true, "message": "REVERT opcode executed" },
  "energy_used": 8624,
  "transaction": { "ret": [{ "ret": "FAILED" }] }
}

With visible: true, message is plain text. Without it, message is hex. Treat a call as successful only when message is empty and transaction.ret is not FAILED:

function constantCallSucceeded(response) {
  const raw = response.result?.message ?? '';
  const message = /^([0-9a-f]{2})+$/i.test(raw) ? Buffer.from(raw, 'hex').toString() : raw;
  const ret = response.transaction?.ret?.[0]?.ret;
  return response.result?.result === true && !message && ret !== 'FAILED';
}

A reverted simulation also reports a low energy_used. Do not size fee_limit from it. For measured USDT transfer energy and fee_limit sizing, see TRON energy for USDT transfers.

Best PracticesCopy Anchor Link

1. Cache Results - Cache view function results appropriately
2. Batch Calls - Group multiple calls for efficiency
3. Handle Errors - Check result.result, result.message and transaction.ret together. A revert keeps result.result true
4. Estimate Energy - Monitor energy_used for optimization
5. Validate Input - Ensure parameters are properly encoded

Related MethodsCopy Anchor Link

• wallet/triggersmartcontract - Execute state-changing functions
• wallet/getcontract - Get contract information
• wallet/estimateenergy - Estimate energy consumption

Need help? Contact support or visit our TRON documentation.