Dapper custom SqlMapper.TypeHandler Parse method not called - dapper

Question

I created a SqlMapper.TypeHandler to map a Customer object into a CreditAccount class as follows:
public class CustomerTypeHandler : SqlMapper.TypeHandler<Customer>
{
public override Customer Parse(object value)
{
throw new NotImplementedException();
}
public override void SetValue(IDbDataParameter parameter, Customer
value)
{
throw new NotImplementedException();
}
}
public class CreditAccount
{
public int AccountId { get; set; }
public Customer Customer{ get; set; }
}
public class Customer
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string MiddleName { get; set; }
}
When I connect to the DB and call a sproc, the CustomerTypeHandler Parse method is never called and my CreditAccount object is populated with the AccountId only. The Customer object is null.
I am calling it as follows:
public async Task<CreditAccount> GetCreditAccount(int accountId)
{
var sql = "MY PROC NAME HERE";
var parameters = new DynamicParameters();
parameters.Add("#AccountId", accountId);
SqlMapper.AddTypeHandler(new CustomerTypeHandler());
using (IDbConnection connection = Connection)
{
connection.Open();
var account = await connection.QueryFirstAsync<CreditAccount>(sql, parameters, commandType: CommandType.StoredProcedure);
return account;
}
}
}
I placed a breakpoint in the Parse method and it is never called.
The database connection works, and I am getting the AccountId.
My environment;
.NET Core 2.2
Dapper 1.50.5
The code is simple enough. I get not exceptions. Any ideas?

Answer 1

A year has passed and now there is no this error in Dapper 2.0.30.
I checked it on jsonb columns in Postgres.
using Dapper;
using Newtonsoft.Json;
using Npgsql;
using System;
using System.Data;
public class CreditAccount
{
public int AccountId { get; set; }
public Customer Customer { get; set; }
}
public class Customer
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string MiddleName { get; set; }
}
public class CustomerJsonObjectTypeHandler : SqlMapper.TypeHandler<Customer>
{
public override void SetValue(IDbDataParameter parameter, Customer value)
{
parameter.Value = (value == null)
? (object)DBNull.Value
: JsonConvert.SerializeObject(value);
parameter.DbType = DbType.String;
}
public override Customer Parse(object value)
{
return JsonConvert.DeserializeObject<Customer>(value.ToString());
}
}
Example using this classes - all work fine.
static void Main(string[] args)
{
using (var connection = GetDefaultConnection())
{
connection.Open();
var customer = new Customer
{
FirstName = "Gaday",
LastName = "Ivanova",
MiddleName = "Petrovich"
};
var jsonData = JsonConvert.SerializeObject(customer);
var strQuery = $"SELECT 10500 as AccountId,'{jsonData}'::jsonb as Customer";
SqlMapper.AddTypeHandler(new CustomerJsonObjectTypeHandler());
try
{
var data = connection.QueryFirst<CreditAccount>(strQuery);
}
catch(Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}