通过在酒吧订购饮料来解释模型视图控制器(MVC) (Model-View-Controller (MVC) Explained Through Ordering Drinks At The Bar)

如果您去过酒吧，那么MVC并不难。 (If you have been to a bar, then MVC ain’t that hard.)

Model-view-controller (MVC) frameworks are a crucial part of building modern web applications. Walk into a room of web developers, and you will likely be bombarded with mentions of Ruby on Rails, Angular or Django.

模型视图控制器(MVC)框架是构建现代Web应用程序的关键部分。走进一个Web开发人员的房间，您可能会被提及Ruby on Rails，Angular或Django的消息轰炸。

More generally, MVC logic can be used to describe almost any web development process that uses a language like PHP, Ruby, Python or JavaScript.

更一般而言，MVC逻辑可用于描述几乎任何使用PHP，Ruby，Python或JavaScript之类的语言的Web开发过程。

永远不会少... (Never the less…)

Many web developers navigate this mysterious world by hacking through the weeds with a smile on their face. When a senior developer or teammate needs to look at the code from one of these developers, they will give an immediate yelp, followed by a swift lecture on common coding practices.

许多网络开发人员通过面带微笑的方式闯入杂草，从而穿越了这个神秘的世界。当高级开发人员或团队成员需要查看其中一个开发人员的代码时，他们会立即给出呼声，随后是关于常见编码实践的快速讲座。

This is no way to go through life! In fact, the MVC pattern in modern web development can be easily explained by ordering a drink from a bartender. And yes, that means if you have been to a bar, then you can understand the major structural pattern shared by all web apps.

这是没有生命的方法！实际上，通过从调酒师订购饮料可以很容易地解释现代Web开发中的MVC模式。是的，这意味着如果您去过酒吧，那么您可以了解所有Web应用程序共享的主要结构模式。

Bravely hacking through the obstacles until reality hits

勇敢地闯入障碍，直到现实降临

What is the MVC Pattern?

什么是MVC模式？

Model: Structures your data in a reliable form and prepares it based on controller’s instructions
模型：以可靠的形式构造数据并根据控制器的指示进行准备
View: Displays data to user in easy-to-understand format, based on the user’s actions
视图：根据用户的操作以易于理解的格式向用户显示数据
Controller: Takes in user commands, sends commands to the model for data updates, sends instructions to view to update interface.
控制器 ：接收用户命令，将命令发送到模型以进行数据更新，发送指令以查看以更新界面。

Or, in diagram form:

或者，以图表形式：

That was boring. Onto the bar.

真无聊。进入酒吧。

初学者Web开发人员进入酒吧… (A beginner web developer enters a bar…)

You enter a bar on a Friday night, and approach the bartender. Since the bar is already crowded, you push through a crowd until you finally catch the bartender’s attention, and you blurt out, “One Manhattan, please!”

您在星期五晚上进入一家酒吧，然后接近酒保。因为酒吧已经很拥挤，所以您要挤满人群，直到最终引起调酒师的注意，然后您脱口而出：“拜托，一个曼哈顿！”

You are the user, and your drink order is the user request. To you, the Manhattan is just your favorite drink, and you pretty reliably know that this will be a sweet and delicious drink.

您是用户，而您的饮料订单是用户请求 。对您来说，曼哈顿只是您最喜欢的饮料，您可以肯定地知道这将是一种甜美可口的饮料。

The bartender gives you a quick nod. To the bartender, the Manhattan is not a tasty drink, it is merely a series of steps:

酒保给你点头。对调酒师来说，曼哈顿不是好喝的酒，它只是一系列步骤：

Grab glass
抓玻璃
Add whiskey
加威士忌
Add vermouth
添加苦艾酒
Add bitters
加苦
Stir drink
搅拌饮料
Add cherry
加樱桃
Ask for credit card and charge.
要求信用卡和收费。

The bartender’s brain is the controller. As soon as you say the word “Manhattan” in a language that they understand, the work begins. This work is similar in nature to making a margarita or strawberry daiquiri, but uses distinct ingredients that will never be confused. The bartender can only use the tools and resources that are behind the bar. This limited tool set is the model, and includes the following:

酒保的大脑是控制者 。只要您以他们理解的语言说出“曼哈顿”一词，便开始工作。这项工作本质上类似于制作玛格丽塔酒或草莓代基里酒，但使用了永不混淆的独特成分。调酒师只能使用酒吧后面的工具和资源。此有限的工具集是模型，包括以下内容：

Bartender’s hands
酒保的手
Shakers/mixing equipment
振动筛/搅拌设备
Liquors
酒类
Mixes
混合
Glasses
眼镜
Garnishes
装饰物

Perhaps at a fancier bar, they might have a robot assistant! Or an automatic drink mixer. It does not matter to your particular bartender, who can only use the available resources.

也许在豪华酒吧里，他们可能会有一个机器人助手！或自动饮料搅拌机。对于您的调酒师来说，这无关紧要，调酒师只能使用可用的资源。

Finally, the finished drink that you can see and consume is the view. The view is built out of the limited options from the model, and arranged and transmitted via the controller (that is, the bartender’s brain).

最后，您可以看到并消费的成品饮料就是视图。 视图是基于模型的有限选项构建的，并通过控制器(即调酒师的大脑)进行排列和传输。

得到教训 (Lessons Learned)

Want another drink? Shouting at your empty glass, the view, will do you absolutely no good. You must talk to the bartender.
要再喝一杯吗？朝空的玻璃杯大喊大叫的景象绝对对您没有好处。你必须和酒保谈谈。
The time spent between the bartender hearing the request and starting to create the drink should be absolutely minimal. This is sometimes known as a “skinny controller”- in other words, the controller should contain a minimal amount of logic, and delegate as much as possible to the model. A great bartender will not only have recipes memorized, but will also prepare the ingredients and tools in a reliable manner every night so that a minimal amount of searching and arranging is needed once the customers start ordering.
在调酒师听到要求和开始制作饮料之间所花费的时间应该绝对是最短的。这有时被称为“瘦控制器”，换句话说，控制器应包含最少数量的逻辑，并尽可能多地委派给模型。一位出色的调酒师不仅会记住食谱，而且每晚都会以可靠的方式准备食材和工具，因此一旦客户开始订购，便只需进行最少的搜索和整理。
Could the bartender pour all the ingredients directly in the customers mouth and expect the customer to swish it around and mix the drink? Yes, possibly I suppose. You want to keep as much of your logic within the model as possible as opposed to within the view. In other words, making the drink behind the bar is preferable to mixing it within the customer’s mouth.
酒保可以直接将所有成分倒入顾客的口中，并期望顾客将其搅匀并混合饮料吗？是的，可能我想。您想要在模型内(而不是视图内)保留尽可能多的逻辑。换句话说，将饮料制作在酒吧后方比将其在顾客口中混合更可取。

If you order a beer, the bartender will hardly need to do anything. Perhaps they will simply remove the cap and hand you the drink. That being said, you still must request the bartender. The beer will not magically appear in front of you.
如果您订购啤酒，酒保几乎不需要做任何事情。也许他们会简单地取下瓶盖，然后将饮料交给您。话虽如此，您仍然必须要求酒保。啤酒不会神奇地出现在您面前。

将其绑定到Web开发 (Tying It Back To Web Development)

Here is how the same process plays out in a modern web app:

这是在现代Web应用程序中如何执行相同的过程：

The user makes a request along a route, let’s say /home.
用户沿着一条路线(例如/ home) 发出请求 。
The controller receives this request and gives a specific set of orders that are related to that route. These instructions could either be for the view to update or serve a certain page, or for the model to perform specific logic. Let’s assume this request has some logic associated with it.
控制器接收到该请求并给出与该路线相关的一组特定订单。这些指令可以用于视图更新或为特定页面提供服务，也可以用于模型执行特定逻辑。假设此请求具有与其相关的某些逻辑。
The model carries out the logic, pulls from a database and sends back a consistent response based on the controller’s instructions.
该模型执行逻辑，从数据库中提取数据，然后根据控制器的指令发送一致的响应。
The controller then passes this data to the view to update the user interface.
然后，控制器将此数据传递到视图以更新用户界面。

Whenever a request comes in, it first must go to the controller before it can be converted into instructions for the view or model. The Ruby on Rails wikipedia article contains a further overview if you are looking for more.

每当有请求进入时，首先必须先进入控制器，然后才能将其转换为视图或模型的指令。如果您正在寻找更多内容，那么Ruby on Rails Wikipedia文章将提供进一步的概述。

Any time you need to learn a new web development framework, you will come across this consistent MVC pattern. And if a particular framework differs from this, you can be sure that the authors will explain their new pattern with references to MVC.

每当您需要学习新的Web开发框架时，都会遇到这种一致的MVC模式。并且，如果某个特定的框架与此不同，则可以确保作者将通过引用MVC来解释其新模式。

This should make learning a heck of a lot easier- once you develop with MVC once, every new framework can fit within your comfort zone.

这应该使学习变得非常容易-一旦使用MVC开发一次，每个新框架都可以适应您的舒适区域。

Did you enjoy this guide? Let me know in the comments!

您喜欢本指南吗？ 在评论中让我知道！