AutoMapper Merge Two Types Ignoring one property

Question

I have this entity:

public class MyType
{
    public Guid Id {get;set;}
    public string Name {get;set;}
}

I want to merge two of these types together, but the source Id needs to be unchanged.

So the objects are filled as such:

From the Database => MyType {
    Id: 012312-42134-12321-12,
    Name: "This Type"
}

From the View => MySecondType {
    Id: null,
    Name: "This Type Changed"
}

And I want to merge MySecondType into MyType but ignore the Id field in the merge.

So I thought maybe doing:

Mapper.Map(mySecondType, myType);

To get the database myType to be filled with the view mySecondType but there is not setting to ignore a property.

Answer 1

When setting up your AutoMapper you could ignore a property:

Mapper
    .CreateMap<MySecondType, MyType>()
    .ForMember(x => x.Id, opt => opt.Ignore());

This being said, it would make far more sense to use a view model in ASP.NET MVC. So you would have your DB bound model MyType with Id and Name properties and have a MyTypeViewModel which will only have a Name property and be used in your view. Then you don't need to be ignoring any properties. This will automatically come from the design of your view models.