映射列表的属性 <T> 使用自动映射器

Question

Using Automapper, I want to map a property that is a List of type Employee using string.Join() to product a comma-delimited string of the names of an employee's rights. Here are the classes I'm using:

public class MappedEmployee
{
    public string Name { get; set; }
    public string RightNames { get; set; }
}

public class Employee
{
    public string Name { get; set; }
    public List<Right> Rights { get; set; }
}

public class Right
{
    public string Name { get; set; }
}

And here is the code I have:

Mapper.CreateMap<Employee, MappedEmployee>()
    .ForMember(d => d.RightNames, o => o.MapFrom(s => s.Rights.SelectMany(r => string.Join(", ", r.Name))));

var employee = new Employee
{
    Name = "Joe Schmoe",
    Rights = new List<Right>
    {
        new Right { Name = "Admin" },
        new Right { Name = "User" },
    }
};

var mappedEmployee = Mapper.Map<Employee, MappedEmployee>(employee);

However, this it's producing the folowing:

System.Linq.Enumerable+<SelectManyIterator>d__14`2[Employee.Right,System.Char]

What can I do do get a comma-delimited string of the Employee's rights?

Answer 1

Try using ResolveUsing instead and putting string.Join before the selection:

Mapper.CreateMap<Employee, MappedEmployee>()
    .ForMember(d => d.RightNames, o => o.ResolveUsing(s => string.Join(", ",s.Rights.Select(r =>  r.Name))));