Expected System.String, got System.Guid

Question

I hope there is a very simple explanation why I get this error.

I am using S # arpArcitecture 1.6. on a 64-bit installation of Windows 7.

Line 3 of the following code gives an error:

{"An identifier of the wrong type is provided. Expected: System.String, received by System.Guid"} System.Exception {NHibernate.TypeMismatchException}

1 public Category GetCategory(Guid id)
2    {
3        Category cat = categoryRepository.Get(id);
4        return cat;
5    }

Supporting information

Table (SQL Server 2008)

CREATE TABLE [dbo].[MasterCategories] (
    [masterCategoryId] [uniqueidentifier] ROWGUIDCOL  NOT NULL,
    [organizationId] [nchar](5) NOT NULL,
    [categoryNumber] [nvarchar](25) NOT NULL
)

Entity definition

public class Category : EntityWithTypedId<Guid>

Free match

public void Override(AutoMapping<Category> mapping)
    {
        mapping.Table("MasterCategories");

        mapping.Id(x => x.Id).Column("masterCategoryId");
        mapping.Map(x => x.Number).Column("categoryNumber");

        mapping.References(x => x.Organization)
            .Column("organizationId")
            .Cascade.All();
    }

Repository interface

public interface ICategoryRepository : IRepositoryWithTypedId<Category,Guid>
{
}

Repository

public class CategoryRepository : 
             RepositoryWithTypedId<Category,Guid>, 
             ICategoryRepository
{ }   

Answer 1

I think your mapping should be like this:

public void Override(AutoMapping<Category> mapping)
{
    mapping.Table("MasterCategories");
    mapping.Id(x => x.Id).Column("masterCategoryId").GeneratedBy.Guid();
    mapping.Map(x => x.Number).Column("categoryNumber");

    mapping.References(x => x.Organization)
            .Column("organizationId")
            .Cascade.All();
}