我目前正在使用viewmodels将我的Views与实际的Model结构分开.
例如,我有一个用户持久性实体和一个包含所有信息的MyProfile viewmodel,用户可以自己更改.
对于从User到MyProfile的转换,我使用的是Automapper.
现在用户回复了他的(更改的)信息后,我需要保存这些信息.但是viewmodel中的信息并不完整,当AutoMapper从viewmodel创建用户持久性实体时,重要信息会丢失.
我不想将此信息公开给视图层,尤其是隐藏的表单元素.
所以我需要一种方法将viewmodel合并到持久性实体中.我可以使用AutoMapper执行此操作,还是必须手动执行此操作?
例:
我的用户类包含ID,名字,姓氏,用户名和密码.用户应该只在他的个人资料中编辑他的名字和姓氏.因此,我的Profileviewmodel包含ID,名字和姓氏.从表单中回发信息后,Automapper从传输的Profileviewmodel创建一个User对象,在此对象中只设置ID,Firstname和Lastname.将此实体提供给我的存储库时,我丢失了用户名和密码信息.
解决方法
So i need a way to merge a viewmodel into a persistence entity. Can I
do that with AutoMapper,or do I have to do it manually?
是的,你可以用AutoMapper做到这一点.例如:
- public class Model
- {
- public int Id { get; set; }
- public string Name { get; set; }
- }
- public class viewmodel
- {
- public string Name { get; set; }
- }
- class Program
- {
- static void Main()
- {
- // define a map (ideally once per appdomain => usually goes in Application_Start)
- Mapper.CreateMap<viewmodel,Model>();
- // fetch an entity from a db or something
- var model = new Model
- {
- Id = 5,Name = "foo"
- };
- // we get that from the view. It contains only a subset of the
- // entity properties
- var viewmodel = new viewmodel
- {
- Name = "bar"
- };
- // Now we merge the view model properties into the model
- Mapper.Map(viewmodel,model);
- // at this stage the model.Id stays unchanged because
- // there's no Id property in the view model
- Console.WriteLine(model.Id);
- // and the name has been overwritten
- Console.WriteLine(model.Name);
- }
- }
打印:
- 5
- bar
并将其转换为典型的ASP.NET MVC模式:
- [HttpPost]
- public ActionResult Update(Myviewmodel viewmodel)
- {
- if (!ModelState.IsValid)
- {
- // validation Failed => redisplay view
- return View(viewmodel);
- }
- // fetch the domain entity that we want to udpate
- DomainModel model = _repository.Get(viewmodel.Id);
- // now merge the properties
- Mapper.Map(viewmodel,model);
- // update the domain model
- _repository.Update(mdoel);
- return RedirectToAction("Success");
- }