# Helper functions

### getMapping

Returns the mapping data of a specific payment reference.

```solidity
function getMapping(bytes memory _paymentReference) public view returns(PaymentERC20 memory) {
        return paymentMapping[_paymentReference];
    }
```

The [paymentMapping](https://github.com/paytr-protocol/contracts/blob/ddf86598e12e641fcb305a3262ebc44f7d623c26/src/Paytr.sol#L98) keeps track of the payment data in the form of a Struct [PaymentERC20](https://github.com/paytr-protocol/contracts/blob/ddf86598e12e641fcb305a3262ebc44f7d623c26/src/Paytr.sol#L68):

```solidity
struct PaymentERC20 {
        uint256 amount;
        uint256 feeAmount;
        uint256 wrapperSharesReceived;
        uint40 dueDate;
        address payer;
        address payee;
        address feeAddress;
        bool shouldPayoutViaRequestNetwork;
}
```

### **Interact with the** getMapping function**:**

{% tabs %}
{% tab title="ethers.js" %}

```javascript
const paytrContract = new ethers.Contract(paytrContractAddress, PaytrABI, signer);

await paytrContract.getMapping(_paymentReference); //pass in bytes

//example
await paytrContract.getMapping("0x494e56332d32343034");
)
```

{% endtab %}

{% tab title="solidity" %}

<pre class="language-solidity"><code class="lang-solidity">interface IPaytr{
function getMapping(bytes memory _paymentReference) external view returns(PaymentERC20 memory) {
}

<strong>IPaytr(deployedPaytrAddress).getMapping(_paymentReference);
</strong>
//example
bytes paymentReference1 = "0x494e56332d32343001";

IPaytr(deployedPaytrAddress).getMapping(paymentReference1);
</code></pre>

{% endtab %}
{% endtabs %}


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