ThirdPartyAPI/GMENepal/Model/GMEBank.cs

using System.ComponentModel.DataAnnotations;

namespace GMENepal.Model
{
    public class GMEBankRequest : GMECommonRequest
    {
        private string _PaymentMethod;

        [Required]
        public string PaymentMethod
        {
            get
            {
                if (_PaymentMethod.ToLower().Equals("cash payment"))
                {
                    return "C";
                }
                return "B";
            }
            set { _PaymentMethod = value; }
        }

        public string ReceivingCountry { get; set; }
    }
}