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---
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title: Create a Web API with ASP.NET Core and Visual Studio for Windows
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author: rick-anderson
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description: Build a web API with ASP.NET Core MVC and Visual Studio for Windows
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ms.author: riande
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ms.custom: mvc
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ms.date: 05/17/2018
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uid: tutorials/first-web-api
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---
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# Create a Web API with ASP.NET Core and Visual Studio for Windows
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By [Rick Anderson ](https://twitter.com/RickAndMSFT ) and [Mike Wasson ](https://github.com/mikewasson )
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This tutorial builds a web API for managing a list of "to-do" items. A user interface (UI) isn't created.
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There are three versions of this tutorial:
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* Windows: Web API with Visual Studio for Windows (This tutorial)
* macOS: [Web API with Visual Studio for Mac ](xref:tutorials/first-web-api-mac )
* macOS, Linux, Windows: [Web API with Visual Studio Code ](xref:tutorials/web-api-vsc )
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<!-- WARNING: The code AND images in this doc are used by uid: tutorials/web - api - vsc, tutorials/first - web - api - mac and tutorials/first - web - api. If you change any code/images in this tutorial, update uid: tutorials/web - api - vsc -->
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[!INCLUDE[intro to web API ](../includes/webApi/intro.md )]
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## Prerequisites
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[!INCLUDE[ ](~/includes/net-core-prereqs-windows.md )]
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## Create the project
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Follow these steps in Visual Studio:
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* From the **File** menu, select **New** > **Project** .
* Select the **ASP.NET Core Web Application** template. Name the project *TodoApi* and click **OK** .
* In the **New ASP.NET Core Web Application - TodoApi** dialog, choose the ASP.NET Core version. Select the **API** template and click **OK** . Do **not** select **Enable Docker Support** .
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### Launch the app
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In Visual Studio, press CTRL+F5 to launch the app. Visual Studio launches a browser and navigates to `http://localhost:<port>/api/values` , where `<port>` is a randomly chosen port number. Chrome, Microsoft Edge, and Firefox display the following output:
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```json
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["value1","value2"]
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```
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If using Internet Explorer, you'll be prompted to save a *values.json* file.
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### Add a model class
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A model is an object representing the data in the app. In this case, the only model is a to-do item.
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In Solution Explorer, right-click the project. Select **Add** > **New Folder** . Name the folder *Models* .
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> [!NOTE]
> The model classes can go anywhere in the project. The *Models* folder is used by convention for model classes.
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In Solution Explorer, right-click the *Models* folder and select **Add** > **Class** . Name the class *TodoItem* and click **Add** .
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Update the `TodoItem` class with the following code:
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[!code-csharp[ ](first-web-api/samples/2.0/TodoApi/Models/TodoItem.cs )]
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The database generates the `Id` when a `TodoItem` is created.
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### Create the database context
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The *database context* is the main class that coordinates Entity Framework functionality for a given data model. This class is created by deriving from the `Microsoft.EntityFrameworkCore.DbContext` class.
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In Solution Explorer, right-click the *Models* folder and select **Add** > **Class** . Name the class *TodoContext* and click **Add** .
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Replace the class with the following code:
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[!code-csharp[ ](first-web-api/samples/2.0/TodoApi/Models/TodoContext.cs )]
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[!INCLUDE[Register the database context ](../includes/webApi/register_dbContext.md )]
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### Add a controller
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In Solution Explorer, right-click the *Controllers* folder. Select **Add** > **New Item** . In the **Add New Item** dialog, select the **API Controller Class** template. Name the class *TodoController* , and click **Add** .
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![Add new Item dialog with controller in search box and web API controller selected ](first-web-api/_static/new_controller.png )
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Replace the class with the following code:
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[!INCLUDE[code and get todo items ](../includes/webApi/getTodoItems.md )]
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### Launch the app
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In Visual Studio, press CTRL+F5 to launch the app. Visual Studio launches a browser and navigates to `http://localhost:<port>/api/values` , where `<port>` is a randomly chosen port number. Navigate to the `Todo` controller at `http://localhost:<port>/api/todo` .
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[!INCLUDE[last part of web API ](../includes/webApi/end.md )]
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[!INCLUDE[jQuery ](../includes/webApi/add-jquery.md )]
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[!INCLUDE[next steps ](../includes/webApi/next.md )]