Basic-usages.md

Mapping to a new object

Mapster creates the destination object and maps values to it.

var destObject = sourceObject.Adapt<Destination>();

Mapping to an existing object

You make the object, Mapster maps to the object.

sourceObject.Adapt(destObject);

Queryable Extensions

Mapster also provides extensions to map queryables.

Important

Avoid calling ProjectToType() before materializing queries from Entity Framework. This is known to cause issues. Instead, call ToList() or ToListAsync() before calling ProjectToType.

using (MyDbContext context = new MyDbContext())
{
    // Build a Select Expression from DTO
    var destinations = context.Sources.ProjectToType<Destination>().ToList();

    // Versus creating by hand:
    var destinations = context.Sources.Select(c => new Destination {
        Id = p.Id,
        Name = p.Name,
        Surname = p.Surname,
        ....
    })
    .ToList();
}