Mapping problem when using Automapper in an Edit form with select list - asp.net-core

Question

I am trying to create an edit form which includes a selectlist that gets the data from the database. I am unable to display the form since I cannot map the viewmodel with the actual model using Automapper.
Contact.cs:
public int ContactId { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string? EmailAddress { get; set; }
public int CompanyId { get; set; }
[ForeignKey("CompanyId")]
public Company Company { get; set; }
ContactEditViewModel.cs:
public int ContactId { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string? EMailAddress { get; set; }
[Range(1, int.MaxValue, ErrorMessage = "Please select a company.")]
public int CompanyId { get; set; }
public SelectList? Company { get; set; }
Edit View
<div class="form-group">
<label asp-for="Company" class="control-label"></label>
<div class="input-group mb-3">
<select asp-for="CompanyId" class="form-select" asp-items="#Model.Company"></select>
</div>
</div>
ContactsController Edit Action:
public async Task<IActionResult> Edit(int? id)
{
if (id == null)
{
return NotFound();
}
var contact = await _context.Contacts.FirstOrDefaultAsync(c => c.ContactId == id);
var model = new ContactEditVM
{
Company = new SelectList(_context.Companies, "CompanyId", "CompanyName"),
};
//var contact = mapper.Map<ContactEditVM>(await contactRepository.GetAsync(id));
mapper.Map(model, contact);
if (contact == null)
{
return NotFound();
}
//ViewData["CompanyId"] = new SelectList(_context.Companies, "CompanyId", "CompanyName", contact.Company);
return View(model);
}
MappingConfiguration
public class MapConfig : Profile
{
public MapConfig()
{
CreateMap<Contact, ContactListVM>().ReverseMap();
CreateMap<Contact, ContactCreateVM>().ReverseMap();
CreateMap<Contact, ContactEditVM>().ReverseMap();
}
}
The error I get is:
AutoMapperMappingException: Missing type map configuration or unsupported mapping.
Mapping types:
SelectList -> Company
Microsoft.AspNetCore.Mvc.Rendering.SelectList -> ENV.Data.Company
Destination Member:
Company
...
If I create a new instance of my viewmodel and assign values to it manually, without using Automapper, it works as intended. So what is wrong with my mapping?

Answer 1

Does it work if you outcomment the "Company" from your Contact.cs and outcomment the "Company" from your ContactEditViewModel.cs?
I think you need to define a mapping which tells autoMapper how to map a "SelectedList?" to a "Company".
For Example:
var autoMapperConfig = new MapperConfiguration(cfg =>
{
cfg.CreateMap<WalletData/*Source*/, BP_WalletDTO/*Destination*/>()
.ForMember(dest => dest.Id, memberOptions => memberOptions.MapFrom(src => src.Id))
.ForMember(dest => dest.Type, memberOptions => memberOptions.MapFrom(src => src.Type))
.ForMember(dest => dest.Attributes, memberOptions => memberOptions.MapFrom(src => new BP_WalletAttributesDTO
{
CryptocoinId = src.Attributes.Cryptocoin_id,
CryptocoinSymbol = src.Attributes.Cryptocoin_symbol,
Balance = src.Attributes.Balance,
IsDefault = src.Attributes.Is_default,
Name = src.Attributes.Name,
PendingTransactionsCount = src.Attributes.Pending_transactions_count,
Deleted = src.Attributes.Deleted,
IsIndex = src.Attributes.Is_index,
}));
});
Maybe this helps