Calling a Web API From a . NET Client (C#)by Mike Wasson. Download Completed Project. This tutorial shows how to call a web API from a .

ASP.NET is a free web framework for building great web sites and applications. This site is the home of the ASP.NET MVC, Web API, and Web Pages source code. API Monitor v2 is currently in Alpha. Installers for both 32-bit and 64-bit versions are now available. Download Now. Save Capture and Monitor Metro apps using the.

NET application, using System. Net. Http. Http. Client.

In this tutorial, we will write an client application that consumes the following web API. Action. HTTP method. Relative URIGet a product by IDGET/api/products/id. Create a new product.

POST/api/products. Update a product. PUT/api/products/id. Delete a product. DELETE/api/products/id. For simplicity, the client application in this tutorial is a Windows console application. Http. Client is also supported for Windows Phone and Windows Store apps.

For more information, see Writing Web API Client Code for Multiple Platforms Using Portable Libraries. Create the Console Application. In Visual Studio, create a new Windows console application and paste in the following code. System. using System. Net. using System.

Net. Http. using System. Net. Http. Headers. System. Threading. Tasks. namespace Http. Client. Sample. . The Main. Run. Async method and blocks until it completes.

This article explains what the Web API is and its basics. Usage § 1 Load JavaScript Files § 1.1. RequireJS takes a different approach to script loading than traditional <script> tags. While it can also run fast and. Internal Server Error. This generic error message is.

The reason for this approach is that most Http. Client methods are async, because they perform network I/O. All of the async tasks will be done inside Run. Async. In a console application, it's OK to block the main thread inside of Main. In a GUI application, you should never block the UI thread. Install the Web API Client Libraries.

Use Nu. Get Package Manager to install the Web API Client Libraries package. From the Tools menu, select Library Package Manager, then select Package Manager Console. In the Package Manager Console window, type the following command: Install- Package Microsoft.

I have a page that allows the user to download a dynamically-generated file. It takes a long time to generate, so I'd like to show a "waiting" indicator. The problem.

Asp. Net. Web. Api. Client. Add a Model Class. Install Ssl Certificate On Direct Admin Reseller. Add the following class to the application: namespace Http. Client. Sample. . We can use Http. Client to read a Product instance from an HTTP response, without having to write a lot of deserialization code. Create and Initialize Http.

Client. Add a static Http. Client property to the Program class. Especially in server applications, creating a new Http. Client instance for every request will exhaust the number of sockets available under heavy loads. This will result in Socket. Exception errors. To initialize the Http.

Client instance, add the following code to the Run. Async method: static async Task Run. Async(). . The method is asynchronous, because it performs network I/O. When the method completes, it returns an Http.

Response. Message that contains the HTTP response. If the status code in the response is a success code, the response body contains the JSON representation of a product. Call Read. As. Async to deserialize the JSON payload to a Product instance.

The Read. Async method is asynchronous because the response body can be arbitrarily large. Http. Client does not throw an exception when the HTTP response contains an error code.

Instead, the Is. Success. Status. Code property is false if the status is an error code. If you prefer to treat HTTP error codes as exceptions, call Http. Response. Message. Ensure. Success. Status. Code on the response object. This method throws an exception if the status code falls outside the range 2.

Note that Http. Client can throw exceptions for other reasons — for example, if the request times out. When Read. As. Async is called with no parameters, it uses a default set of media formatters to read the response body. The default formatters support JSON, XML, and Form- url- encoded data. Instead of using the default formatters, you can provide a list of formatters to the Read. Async method, which is useful if you have a custom media- type formatter: var formatters = new List< Media.

Type. Formatter> () . If the request succeeds, it should return a 2. Created) response, with the URL of the created resources in the Location header. Sending a PUT Request to Update a Resource. The following code sends a PUT request to update a product. Task< Product> Update. Product. Async(Product product).

The code is very simple and doesn't include much error handling, but it shows the basic CRUD operations using Http. Client. using System.

System. Net. using System. Net. Http. using System.

Net. Http. Headers. System. Threading. Tasks. namespace Http.