GetAlreadyUsedCredit.cs

// For complete examples and data files, please go to https://github.com/groupdocs-annotation/GroupDocs.Annotation-for-.NET
/// <summary>
/// Number of already used credits
/// </summary>
public static decimal GetAlreadyUsedCredit()
{
    string PublicKey = ""; // Your public license key
    string PrivateKey = ""; // Your private license key
    Metered metered = new Metered();
    metered.SetMeteredKey(PublicKey, PrivateKey);
    //Retrieves amount of already used credits
    return Metered.GetConsumptionCredit();
}