# Problem with signature

**URL:** <https://community.rapyd.net/t/problem-with-signature/195>\
**Category:** ⚙️ API\
**Created:** [April 30, 2021, 3:06pm UTC](https://community.rapyd.net/t/problem-with-signature/195 "2021-04-30T15:06:10Z")\
**Posts on this page:** 1\
**Showing post:** 4

<div class="post-metadata">

**Author:** ![onesoft](https://sea2.discourse-cdn.com/flex016/user_avatar/community.rapyd.net/onesoft/32/832_2.png) [@onesoft](https://community.rapyd.net/u/onesoft)\
**Post date:** [May 1, 2021, 2:17am UTC](https://community.rapyd.net/t/problem-with-signature/195/4 "2021-05-01T02:17:56Z")

</div>

This was a fun challenge 😒

Here is my current solution for c#:

RoundedCurrencyAmount to hold the amount and take care of the rounding

```
public class RoundedCurrencyAmount
{
    private static readonly string[] _threeDigitsCurrencies = {"BHD", "IQD", "JOD", "KWD", "LYD", "OMR", "TND"};
    private static readonly string[] _fourDigitsCurrencies = { "CLF", "UYW"};

    private readonly decimal _amountTotal;

    public RoundedCurrencyAmount(decimal amountTotal, string currencyIsoCode)
    {
        CurrencyIsoCode = currencyIsoCode;
        _amountTotal = amountTotal;
    }

    public string CurrencyIsoCode { get; private set; }

    [Localizable(false)]
    public override string ToString()
    {
        if (_amountTotal % 1 == 0)
            return _amountTotal.ToString("F0", CultureInfo.InvariantCulture);

        if(_threeDigitsCurrencies.Contains(CurrencyIsoCode))
            return _amountTotal.ToString("F3", CultureInfo.InvariantCulture);

        if (_fourDigitsCurrencies.Contains(CurrencyIsoCode))
            return _amountTotal.ToString("F4", CultureInfo.InvariantCulture);

        return _amountTotal.ToString("F2", CultureInfo.InvariantCulture);
    }
}

```

The request class:

```
public class RapydCreateCheckoutPageRequest
{
    public RapydCreateCheckoutPageRequest(decimal amountTotal, string currencyCode)
    {
        Amount = new RoundedCurrencyAmount(amountTotal, currencyCode);
    }

    /// <summary>
    /// The amount of the payment, in units of the currency defined in currency. 
    /// Decimal, including the correct number of decimal places for the currency exponent, as defined in ISO 4217:2015. 
    /// If the amount is a whole number, use an integer and not a decimal
    /// </summary>
    [JsonProperty(@"amount")]
    public RoundedCurrencyAmount Amount { get; }
  ....
}

```

For serialization with newtonsoft:

```
class RoundedCurrencyAmountJsonConverter : JsonConverter
{
    public override bool CanRead => false;

    public override object ReadJson(
           JsonReader reader, 
           Type objectType, 
            object existingValue, 
            JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(RoundedCurrencyAmount);
    }

    public override void WriteJson(
                   JsonWriter writer, object value, JsonSerializer serializer)
    {
        var item = (RoundedCurrencyAmount)value;
        writer.WriteRawValue(item.ToString());
    }
}

```

and finally the updated sterilizeBody function:

```
private static string SerializeBody(object from)
{
    var s = from as string;
    if(s != null)
        return s;

    return from != null ? JsonConvert.SerializeObject(
            from,
            Formatting.None,
                
            new JsonSerializerSettings
            {
                Converters = new List<JsonConverter> { new RoundedCurrencyAmountJsonConverter()},
                NullValueHandling = NullValueHandling.Ignore,
            }
        ) : string.Empty;
    }
```

---

_[View the full topic](https://community.rapyd.net/t/problem-with-signature/195)._