> For the complete documentation index, see [llms.txt](https://docs.usemoon.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usemoon.ai/additional-moon-packages-7ca327c0bb2846d88b8ba5bc6caeaead/moonup-moon-api/erc721.md).

# Erc721

The `Erc721` class from the `@moonup/moon-api` package provides methods to interact with ERC-721 tokens.

### Initialization

To use the `Erc721` class, you need to create an instance of it by passing an instance of the `HttpClient` class to its constructor. The `HttpClient` class is also part of the `@moonup/moon-api` package and provides a convenient way to make HTTP requests.

Here's an example of how to create an instance of the `Erc721` class:

```javascript
import { HttpClient, Erc721 } from '@moonup/moon-api';

const http = new HttpClient({
  baseUrl: 'https://beta.usemoon.ai',
  securityWorker: async (securityData) => {
    return {
      headers: {
        Authorization: `Bearer ${securityData.token}`,
      },
    };
  },
});

const erc721 = new Erc721(http);
```

### Methods

The `Erc721` class provides the following methods:

1. `approve(name: string, data: Erc721Request, params?: RequestParams): Promise<ApproveData>`

   * Approves a spender to transfer a specific token on behalf of the owner.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `ApproveData`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     to: 'spender_address',
     token_id: 'token_id',
     contract_address: 'contract_address',
   };
   const result = await erc721.approve(name, data);
   console.log(result);
   ```
2. `balanceOf(name: string, data: Erc721Request, params?: RequestParams): Promise<BalanceOfResult>`

   * Retrieves the balance of a specific account for a given ERC-721 token.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `BalanceOfResult`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     owner: 'account_address',
     contract_address: 'contract_address',
   };
   const result = await erc721.balanceOf(name, data);
   console.log(result);
   ```
3. `getApproved(name: string, data: Erc721Request, params?: RequestParams): Promise<GetApprovedData>`

   * Retrieves the address of the spender that is approved to transfer a specific token.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `GetApprovedData`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     token_id: 'token_id',
     contract_address: 'contract_address',
   };
   const result = await erc721.getApproved(name, data);
   console.log(result);
   ```
4. `isApprovedForAll(name: string, data: Erc721Request, params?: RequestParams): Promise<IsApprovedForAllResult>`

   * Checks if an operator is approved to transfer all tokens of a specific owner.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `IsApprovedForAllResult`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     owner: 'account_address',
     operator: 'operator_address',
     contract_address: 'contract_address',
   };
   const result = await erc721.isApprovedForAll(name, data);
   console.log(result);
   ```
5. `name(name: string, data: Erc721Request, params?: RequestParams): Promise<NameData>`

   * Retrieves the name of a given ERC-721 token.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `NameData`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     contract_address: 'contract_address',
   };
   const result = await erc721.name(name, data);
   console.log(result);
   ```
6. `ownerOf(name: string, data: Erc721Request, params?: RequestParams): Promise<OwnerOfData>`

   * Retrieves the owner of a specific token.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `OwnerOfData`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     token_id: 'token_id',
     contract_address: 'contract_address',
   };
   const result = await erc721.ownerOf(name, data);
   console.log(result);
   ```
7. `safeTransferFrom(name: string, data: Erc721Request, params?: RequestParams): Promise<SafeTransferFromResult>`

   * Transfers a specific token from one account to another.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `SafeTransferFromResult`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     from: 'sender_address',
     to: 'recipient_address',
     token_id: 'token_id',
     contract_address: 'contract_address',
   };
   const result = await erc721.safeTransferFrom(name, data);
   console.log(result);
   ```
8. `setApprovalForAll(name: string, data: Erc721Request, params?: RequestParams): Promise<SetApprovalForAllResult>`

   * Approves or revokes an operator to transfer all tokens of a specific owner.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `SetApprovalForAllResult`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     owner: 'account_address',
     operator: 'operator_address',
     approved: true,
     contract_address: 'contract_address',
   };
   const result = await erc721.setApprovalForAll(name, data);
   console.log(result);
   ```
9. `symbol(name: string, data: Erc721Request, params?: RequestParams): Promise<SymbolData>`

   * Retrieves the symbol of a given ERC-721 token.
   * `name` is a string that represents the name of the ERC-721 token.
   * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
   * `params` is an optional object of type `RequestParams` that can be used to customize the request.
   * Returns a promise that resolves to an object of type `SymbolData`.

   Example usage:

   ```javascript
   const name = 'my_token';
   const data = {
     contract_address: 'contract_address',
   };
   const result = await erc721.symbol(name, data);
   console.log(result);
   ```
10. `tokenUri(name: string, data: Erc721Request, params?: RequestParams): Promise<TokenUriData>`

    * Retrieves the URI of a specific token.
    * `name` is a string that represents the name of the ERC-721 token.
    * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
    * `params` is an optional object of type `RequestParams` that can be used to customize the request.
    * Returns a promise that resolves to an object of type `TokenUriData`.

    Example usage:

    ```javascript
    const name = 'my_token';
    const data = {
      token_id: 'token_id',
      contract_address: 'contract_address',
    };
    const result = await erc721.tokenUri(name, data);
    console.log(result);
    ```
11. `transfer(name: string, data: Erc721Request, params?: RequestParams): Promise<TransferData>`

    * Transfers a specific token from the sender's account to a recipient's account.
    * `name` is a string that represents the name of the ERC-721 token.
    * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
    * `params` is an optional object of type `RequestParams` that can be used to customize the request.
    * Returns a promise that resolves to an object of type `TransferData`.

    Example usage:

    ```javascript
    const name = 'my_token';
    const data = {
      from: 'sender_address',
      to: 'recipient_address',
      token_id: 'token_id',
      contract_address: 'contract_address',
    };
    const result = await erc721.transfer(name, data);
    console.log(result);
    ```
12. `transferFrom(name: string, data: Erc721Request, params?: RequestParams): Promise<TransferFromData>`

    * Transfers a specific token from a sender's account to a recipient's account on behalf of the sender.
    * `name` is a string that represents the name of the ERC-721 token.
    * `data` is an object of type `Erc721Request` that contains the necessary information to make the request.
    * `params` is an optional object of type `RequestParams` that can be used to customize the request.
    * Returns a promise that resolves to an object of type `TransferFromData`.

    Example usage:

    ```javascript
    const name = 'my_token';
    const data = {
      from: 'sender_address',
      to: 'recipient_address',
      token_id: 'token_id',
      contract_address: 'contract_address',
    };
    const result = await erc721.transferFrom(name, data);
    console.log(result);
    ```

These methods can be used to perform various operations on ERC-721 tokens, such as checking token balances, approving spenders, transferring tokens, and more. The `Erc721` class is a part of the `@moonup/moon-api` package, which provides a convenient way to interact with the Moon API.

The `contract_address` and `token_id` properties are required for most of the `Erc721` class methods, as they are used to identify the specific ERC-721 token contract and token with which to interact. Without the `contract_address` and `token_id` properties, the method may not be able to correctly identify the token contract and token and may return incorrect results.