TRC-721 Contract Interaction

1.Query the Token Name

Call the name() function of the TRC721 contract to get the token name.

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_name() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let trc721name = await contract.name().call();
        console.log('name: ', trc721name);
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_name()

Return results：

name:  TRC721TEST

2.Query the Token Symbol

Call the symbol() function of the TRC721 contract to get the token symbol.

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_symbol() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let trc721symbol = await contract.symbol().call();
        console.log('symbol: ', trc721symbol);
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_symbol()

Return results:

symbol:  TEST

3.Query the Balance

Call the balanceOf() function of the TRC721 contract to get the balance of tokens for the specified account.

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_balanceOf() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address
    var address = "TA1g2WQiXbU5GnYBTJ5Cp22dvSjT3ug9uK";

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let result = await contract.balanceOf(address).call();
        console.log('balance: ', tronWeb.toDecimal(result));
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_balanceOf()

Return results:

balance:  1

4.NFT Transfer

Call the tranferFrom() function of the TRC721 contract for NFT transfers

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_transferFrom() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use send to execute a non-pure or modify smart contract method on a given smart contract that modify or change values on the blockchain.
        // These methods consume resources(bandwidth and energy) to perform as the changes need to be broadcasted out to the network.
        await contract.transferFrom(
            "TA1g2WQiXbU5GnYBTJ5Cp22dvSjT3ug9uK", //address _from
            "TM8vRhebJD7zeoBLWAnr9SrYrhWNrHjBgC", //address _to
            666 //uint256 tokenId
        ).send({
            feeLimit: 100000000
        }).then(output => {console.log('- transferFrom hash:', output, '\n');});
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_transferFrom()

Return results:

- transferFrom hash: 9f4d10713cb0406adb7c729013b941d35597afeeba56faf2a1bc7647fc0a92bd

Note: The above result is the transfer transaction hash, you can check the transaction details via Nile tronscan browse

5.Approve the Control of an NFT to Another Address

Call the approve() function of the TRC721 contract to grant NFT access to other addresses

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_approve() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use send to execute a non-pure or modify smart contract method on a given smart contract that modify or change values on the blockchain.
        // These methods consume resources(bandwidth and energy) to perform as the changes need to be broadcasted out to the network.
        await contract.approve(
            "TA1g2WQiXbU5GnYBTJ5Cp22dvSjT3ug9uK", //address _spender
            666 //uint256 tokenId
        ).send({
            feeLimit: 100000000
        }).then(output => {console.log('- approve hash:', output, '\n');});
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_approve()

Return results:

- approve hash: d7cb1451ed962667f3e24323655dadd8c650ee80d171ea5e44ea97b97eaa3118 

Note: The above result is the authorized transaction hash, you can check the transaction details through Nile tronscan browser

6.Query All NFT information of a TRC-721 Contract of a Specific Address

(1).Call the function of balanceOf(address _owner) to query the number of NFT holdings

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_balanceOf() {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address
    var address = "TM8vRhebJD7zeoBLWAnr9SrYrhWNrHjBgC";

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let result = await contract.balanceOf(address).call();
        console.log('result: ', tronWeb.toDecimal(result));
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_balanceOf()

Return results:：

result:  2
Note: The returned result indicates that the above query address holds a quantity of 2.

(2).Call the function of tokenOfOwnerByIndex(address _owner, uint256 _index) to traverse all token_ids

The number of NFTs held by the above address is 2, so the index of the query is 0 and 1 respectively.

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_tokenOfOwnerByIndex(index) {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let token_id = await contract.tokenOfOwnerByIndex(
            "TM8vRhebJD7zeoBLWAnr9SrYrhWNrHjBgC", // address owner
            index //uint256 index
            ).call();
        console.log('token_id: ', tronWeb.toDecimal(token_id));
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_tokenOfOwnerByIndex(0)
trc721_tokenOfOwnerByIndex(1)

Return results:

token_id:  666
token_id:  555

(3).Call the function of tokenURI(uint256 _tokenId) to query the details of every NFT.

const TronWeb = require('tronweb')

const HttpProvider = TronWeb.providers.HttpProvider;
const fullNode = new HttpProvider("https://nile.trongrid.io");
const solidityNode = new HttpProvider("https://nile.trongrid.io");
const eventServer = new HttpProvider("https://nile.trongrid.io");
const privateKey = "your private key";
const tronWeb = new TronWeb(fullNode,solidityNode,eventServer,privateKey);

async function trc721_tokenURI(tokenid) {
    const trc721ContractAddress = "TRio4FwnDvtYN2ogss6Qm7Hn2EaTLwWMNs";//contract address

    try {
        let contract = await tronWeb.contract().at(trc721ContractAddress);
        //Use call to execute a pure or view smart contract method.
        // These methods do not modify the blockchain, do not cost anything to execute and are also not broadcasted to the network.
        let tokenURI = await contract.tokenOfOwnerByIndex(
            tokenid //uint256 tokenid
            ).call();
        console.log(tokenid + ' tokenURI:', tokenURI);
    } catch(error) {
        console.error("trigger smart contract error",error)
    }
}
trc721_tokenURI(666)
trc721_tokenURI(555)

Return results:

666 tokenURI:  https://gateway.btfs.io/btfs/QmWq4cp588QD8tzrSxvPs2bGikDdKyA35BT3iysBcP1jFD
555 tokenURI: https://gateway.btfs.io/btfs/QmWq4cp588QD8tzrSxvPs2bGikDdKyA35BT3iysBcP1jFD