MVC模式的大写小写VS模式 [英] mvc uppercase Model vs lowercase model

问题描述

我工作的一个MVC 5项目，MVC很新。我注意到，在code此行：

I'm working on a MVC 5 project, very new to MVC. I noticed this line in the code:

@Html.DropDownListFor(model => model.ContractorId, Model.Contractors)

页面顶部的指令是：

the directive on the top of the page is:

@model Project.Models.ContractViewModel

该ContractViewModel类确实有一个承包商在它的对象。

The ContractViewModel class does have a Contractors object in it.

public IEnumerable<SelectListItem> Contractors

我只是对资本M（Model.Contractors）有点糊涂，不模型总是指在@model传递的对象？然后使用Model.Contractors和model.Contractors之间的区别是什么呢？

I'm just a little confused on the capital M (Model.Contractors), does Model always refer to the object passed in the @model? Then what is the difference between using Model.Contractors and model.Contractors?

推荐答案

型号实际上重新presents这是您的模型类的一个实例并模型一个别名拉姆达前pression。

Model actually represents an instance of the class that is your model and model is an alias for lambda expression.

当你写 @Model 在你看来，你所使用的是从控制器操作传递 ContractViewModel 的对象，如果不从View通过它可以为空和访问模型的任何财产可以扔的空引用异常并写 Model.Contractors 基本上你意味着 ContractViewModel.Contractors

When you write @Model in your view you are using the object of ContractViewModel which is passed from Controller action, if it is not passed from View it can be null and accessing any property of Model can throw Null Reference Exception and writing Model.Contractors you basically mean ContractViewModel.Contractors

和当你写一个HTML帮手，你需要为它编写一个别名，它不是强制性的写模式你可以写任何东西。

and when you write a html helper you need to write an alias for it, its not mandatory to write model you can write anything.

例如：

@Html.DropDownListFor(m=> m.ContractorId, Model.Contractors)

这只是进入里面的模特属性别名 HTML辅助

当你写 @model Project.Models.ContractViewModel 在视图顶部这是一个不同的事情，在这种情况下，我们正在定义来看，它会模型采取 Project.Models.ContractViewModel ，其实我们认为现在是强类型的类实例 Project.Models.ContractViewModel 。

When you write @model Project.Models.ContractViewModel at the top of View that is a different thing, in this case we are defining the model of view that it will take instance of Project.Models.ContractViewModel , actually our view is now strongly typed to instance of class Project.Models.ContractViewModel.

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