how to create an asp.net web api project in visual studio 2017

https://docs.microsoft.com/en-us/aspnet/web-api/overview/getting-started-with-aspnet-web-api/tutorial-your-first-web-api

Create a Web API Project

1.新建项目

2.选择Empty，然后web api

You can also create a Web API project using the "Web API" template. The Web API template uses ASP.NET MVC to provide API help pages. I'm using the Empty template for this tutorial because I want to show Web API without MVC. In general, you don't need to know ASP.NET MVC to use Web API.

Adding a Model

Adding a Controller

If you have used ASP.NET MVC, you are already familiar with controllers. Web API controllers are similar to MVC controllers, but inherit the ApiController class instead of the Controller class.

You don't need to put your controllers into a folder named Controllers. The folder name is just a convenient way to organize your source files.

https://stackoverflow.com/questions/22589245/difference-between-mvc-5-project-and-web-api-project

Basically, a Web API controller is an MVC controller, which uses HttpMessageResponse as the base type of its response, instead of ActionResponse. They are the same in most other respects. The main difference between the project types is that the MVC Application project type adds web specific things like default CSS, JavaScript files and other resources needed for a web site, which are not needed for an API.

MVC is used for creating web sites. In this case Controllers usually return a View (i.e. HTML response) to browser requests. Web APIs on the other hand are usually made to be consumed by other applications. If you want to allow other applications to access your data / functionality, you can create a Web API to facilitate this access. For example, Facebook has an API in order to allow App developers to access information about users using the App. Web APIs don't have to be for public consumption. You can also create an API to support your own applications. For example, we created a Web API to support the AJAX functionality of our MVC web site.

Microsoft changed the way they present the different templates. Now instead of using different templates for different project types, they encourage developers to mix ASP.NET technologies inside the same project as needed. Microsoft calls this vNext.

UPDATE: For ASP.NET Core, Web API has been integrated into the MVC 6 project type and the ApiController class is consolidated合并 into the Controller class. Further details at: https://wildermuth.com/2016/05/10/Writing-API-Controllers-in-ASP-NET-MVC-6

https://stackoverflow.com/questions/9494966/difference-between-apicontroller-and-controller-in-asp-net-mvc

Use Controller(mvc) to render your normal views. ApiController action only return data that is serialized and sent to the client.

Quote:

Note If you have worked with ASP.NET MVC, then you are already familiar with controllers. They work similarly in Web API, but controllers in Web API derive from the ApiController class instead of Controller class. The first major difference you will notice is that actions on Web API controllers do not return views, they return data.

ApiControllers are specialized in returning data. For example, they take care of transparently serializing the data into the format requested by the client. Also, they follow a different routing scheme by default (as in: mapping URLs to actions), providing a REST-ful API by convention约定.

You could probably do anything using a Controller instead of an ApiController with the some(?) manual coding. In the end, both controllers build upon the ASP.NET foundation. But having a REST-ful API is such a common requirement today that WebAPI was created to simplify the implementation of a such an API.

It's fairly simple to decide between the two:

if you're writing an HTML based web/internet/intranet application - maybe with the occasional AJAX call returning json here and there - stick with MVC/Controller.

If you want to provide a data driven/REST-ful interface to a system, go with WebAPI. You can combine both, of course, having an ApiController cater AJAX calls from an MVC page.

To give a real world example: I'm currently working with an ERP system that provides a REST-ful API to its entities. For this API, WebAPI would be a good candidate. At the same time, the ERP system provides a highly AJAX-ified web application that you can use to create queries for the REST-ful API. The web application itself could be implemented as an MVC application, making use of the WebAPI to fetch meta-data etc.

Deploy the asp.net web api to IIS

1.Create a new Application pool on IIS named as Chuck_WebApi

2.Create a new Application on IIS named as Chuck_WebApi, and use the created Application pool in step 1

use fiddler's composer test the url

test with wrong controller  http://localhost/Chuck_WebApi/api/product/1

request

GET http://localhost/Chuck_WebApi/api/product/1 HTTP/1.1
User-Agent: Fiddler
Host: localhost
Content-Length: 0

response

HTTP/1.1 404 Not Found
Cache-Control: no-cache
Pragma: no-cache
Content-Type: application/json; charset=utf-8
Expires: -1
Server: Microsoft-IIS/10.0
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
Date: Thu, 17 Jan 2019 08:58:52 GMT
Content-Length: 197

{"Message":"No HTTP resource was found that matches the request URI 'http://localhost/Chuck_WebApi/api/product/1'.","MessageDetail":"No type was found that matches the controller named 'product'."}

test the root path

request

GET http://localhost/Chuck_WebApi/ HTTP/1.1
User-Agent: Fiddler
Host: localhost
Content-Length: 0

response

HTTP/1.1 403 Forbidden
Cache-Control: private
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/10.0
X-Powered-By: ASP.NET
Date: Thu, 17 Jan 2019 09:14:25 GMT
Content-Length: 5213

只截取了一部分回复

<title>IIS 10.0 Detailed Error - 403.14 - Forbidden</title

test the products

request

GET http://localhost/Chuck_WebApi/api/products HTTP/1.1
User-Agent: Fiddler
Host: localhost
Content-Length: 0

response

HTTP/1.1 200 OK
Cache-Control: no-cache
Pragma: no-cache
Content-Type: application/json; charset=utf-8
Expires: -1
Server: Microsoft-IIS/10.0
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
Date: Thu, 17 Jan 2019 09:23:39 GMT
Content-Length: 182

[{"Id":1,"Name":"Tomato Soup","Category":"Groceries","Price":1.0},{"Id":2,"Name":"Yo-yo","Category":"Toys","Price":3.75},{"Id":3,"Name":"Hammer","Category":"Hardware","Price":16.99}]