• Ankr Gaming
• Unity SDK
• Interacting with Blockchain
• Interacting with Smart Contract

Interact with smart contract

You can interact with a smart contract using these two SDK functions:

• GetData() — reads from the smart contract’s view functions via the public RPC. Calling view functions doesn't cost any gas.

• CallMethod() — writes to the contract, changing the blockchain state. Calling write function costs varying amount of gas.

GetData()

Gets data from a smart contract’s view functions. GetData() is included in the IContract interface.

Task<TReturnType> GetData<TFieldData, TReturnType>(TFieldData requestData = null)
			where TFieldData : FunctionMessage, new();

Example

Getting the balance of the owner's address via BalanceOf() from an ERC721 contract. Here GetData() function is combined with a FunctionMessage that was created specifically for this function.

public static UniTask<BigInteger> BalanceOf(this IContract contract, string owner)
{
	var balanceOfMessage = new BalanceOfMessage
	{
		Owner = owner
	};

	return contract.GetData<BalanceOfMessage, BigInteger>(balanceOfMessage).AsUniTask();
}

[Function("balanceOf", "uint256")]
public class BalanceOfMessage : FunctionMessage
{
	[Parameter("address", "_owner", 1)]
	public string Owner { get; set; }
}

CallMethod()

Writes to a contract. Writing actions costs gas. CallMethod() is included in the IContract interface.

public async Task<string> CallMethod(string methodName, object[] arguments = null, string gas = null,
			string gasPrice = null, string nonce = null)

The arguments array that is passed as an argument to the function must correspond to the arguments passed to the smart contract function you effectively want to call.

Example

Transferring a token from an address to an address via SafeTransferFrom() from an ERC721 contract.

public static UniTask<string> SafeTransferFrom(this IContract contract, string from, string to,
	BigInteger tokenId, byte data)
{
	const string safeTransferFromMethodName = "safeTransferFrom";

	return contract.CallMethod(safeTransferFromMethodName, new object[]
	{
		from,
		to,
		tokenId,
		data
	}).AsUniTask();
}