在ASP.Net MVC视图模型嵌套模型的验证 [英] Validation of nested models in view model in ASP.Net MVC

问题描述

我有一个公司模型的应用程序。本公司模式有一个导航属性​​到一个地址模型（一个一对一的关系）：

I have an application with a Company model. The Company model has a navigation property to an Address model (one-to-one relationship):

Company.cs

public class Company
{
    public int CompanyID { get; set; }
    public string Name { get; set; }

    // Snip...

    public virtual Address Address { get; set; }
}

我创建了一个视图模型来处理编辑，细节，并创建行动：

I've created a view model to handle the edit, detail, and create actions:

CompanyViewModel.cs

public class CompanyViewModel
{
    public int CompanyID { get; set; }

    [Required]
    [StringLength(75, ErrorMessage = "Company Name cannot exceed 75 characters")]
    public string Name { get; set; }

    // Snip...

    public Address Address { get; set; }
}

我在我的控制器映射来回模型和视图模型之间使用AutoMapper，一切工作正常。不过，我现在想的地址对象使用验证 - 我不想没有地址为present创建一家公司做

I'm using AutoMapper in my controller to map back and forth between the model and view model, and everything is working properly. However, I now want to use validation on the address object - I do not want a company to be created without an address being present.

我首先想到的是简约路线 - 我试图把一个[必需]注释的地址属性。这并没有做任何事情。

My first thought was the simple route - I tried putting a '[Required]' annotation on the Address property. This didn't do anything.

我当时以为这将是更好废除Address属性和抽象，在视图模型数据，所以我加了属性的视图模式都在我的地址类的属性：

I then thought it would be better to do away with the Address property and abstract that data in the view model, so I added properties to the view model for all the properties in my Address class:

public string Address1 { get; set; }
public string Address2 { get; set; }
public string City { get; set; }
public string PostalCode { get; set; }
// etc....

这似乎是很好的做法，但现在我的AutoMapper不能将这些属性的公司类的地址映射对象，所以我不得不在控制器手动映射：

This seemed like good practice, but now my AutoMapper can't map these properties to the Company class' Address object, so I had to manually map in the controller:

public ActionResult Details(int id = 0)
{
    // Snip code retrieving company from DB

    CompanyViewModel viewModel = new CompanyViewModel();
    viewModel.Name = company.Name;
    viewModel.Address1 = company.Address.Address1;

    // Snip...    

    return View(viewModel);
}

这导致了很多额外的code在我的控制器，而不是一个很好的单行AutoMapper声明......有啥处理这个（在视图模型嵌套模型的验证）的正确方法？

This leads to a lot of extra code in my controller instead of a nice one-line AutoMapper statement...so what's the right way to deal with this (validation of nested models in a view model)?

它是很好的做法，Address属性直接在视图模型暴露，或更好的抽象出来，独立的属性，如我这样做？

Is it good practice to expose the Address property directly in the view model, or better to abstract it out with separate properties like I have done?

能否AutoMapper工作的情况下源和目标并不完全匹配？

Can AutoMapper work in a situation where source and destination are not exact matches?

推荐答案

如果你想automapper要能够在不显式指定映射模型，从你的属性映射到您的视图模型，你必须使用flattenting公约 ：意味着你必须与它的属性名称拼接导航属性的名称。

if you want automapper to be able to map your properties from model to your viewmodel without specifying the mappings explicitly, you've got to use the "flattenting convention" : means that you must concatenate the navigation property's name with its property names.

所以，你的视图模型应该包含

So your ViewModel should contain

public int CompanyID { get; set; }

    [Required]
    [StringLength(75, ErrorMessage = "Company Name cannot exceed 75 characters")]
    public string Name { get; set; }

    // Snip...
    //Address is the navigation property in Company, Address1 is the desired property from Address
    public string AddressAddress1 { get; set; }
    public string AddressAddress2 { get; set; }
    public string AddressCity { get; set; }
    public string AddressPostalCode { get; set; }
}

对了，你也可以告诉AutoMapper映射不明确尊重命名约定属性：

by the way, you can also tell AutoMapper to map properties which don't respect the naming convention explicitly :

Mapper.CreateMap<Company, CompanyViewModel>()
.ForMember(dest => dest.Address1, opt => opt.MapFrom(src => src.Address.Address1));

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