> For the complete documentation index, see [llms.txt](https://raviram.gitbook.io/webapi-module-1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://raviram.gitbook.io/webapi-module-1/create-pizza-api/implement-crud.md).

# Implement CRUD

## Implement CRUD operation

Let's continue extending our web API controller to add the ability to create (`POST`), update (`PUT`), and delete (`DELETE`) pizza from our inventory.

### Add a pizza <a href="#add-a-pizza" id="add-a-pizza"></a>

Let's enable a pizza to be added through the web API by using a `POST` method.

Replace the `// POST action` comment in *Controllers/PizzaController.cs* with the following code:

```csharp
[HttpPost]
public IActionResult Create(Pizza pizza)
{            
    PizzaService.Add(pizza);
    return CreatedAtAction(nameof(Create), new { id = pizza.Id }, pizza);
}
```

The preceding action:

* Responds only to the HTTP `POST` verb, as denoted by the `[HttpPost]` attribute.
* Inserts the request body's `Pizza` object into the in-memory cache.

&#x20;Note

Because the controller is annotated with the `[ApiController]` attribute, it's implied that the `Pizza` parameter will be found in the request body.

The first parameter in the `CreatedAtAction` method call represents an action name. The `nameof` keyword is used to avoid hard-coding the action name. `CreatedAtAction` uses the action name to generate a `location` HTTP response header with a URL to the newly created pizza.

### Modify a pizza <a href="#modify-a-pizza" id="modify-a-pizza"></a>

Now, let's enable a pizza to be updated through the web API by using a `PUT` method.

Replace the `// PUT action` comment in *Controllers/PizzaController.cs* with the following code:

```csharp
[HttpPut("{id}")]
public IActionResult Update(int id, Pizza pizza)
{
    if (id != pizza.Id)
        return BadRequest();
           
    var existingPizza = PizzaService.Get(id);
    if(existingPizza is null)
        return NotFound();
   
    PizzaService.Update(pizza);           
   
    return NoContent();
}
```

The preceding action:

* Responds only to the HTTP PUT verb, as denoted by the `[HttpPut]` attribute.
* Requires that the `id` parameter's value is included in the URL segment after `pizza/`.
* Returns `IActionResult`, because the `ActionResult` return type isn't known until runtime. The `BadRequest`, `NotFound`, and `NoContent` methods return `BadRequestResult`, `NotFoundResult`, and `NoContentResult` types, respectively.

&#x20;Note

Because the controller is annotated with the `[ApiController]` attribute, it's implied that the `Pizza` parameter will be found in the request body.

### Remove a pizza <a href="#remove-a-pizza" id="remove-a-pizza"></a>

Finally, let's enable a pizza to be removed through the web API by using a `DELETE` method.

Replace the `// DELETE action` comment in *Controllers/PizzaController.cs* with the following code:

```csharp
[HttpDelete("{id}")]
public IActionResult Delete(int id)
{
    var pizza = PizzaService.Get(id);
   
    if (pizza is null)
        return NotFound();
       
    PizzaService.Delete(id);
   
    return NoContent();
}
```

The preceding action:

* Responds only to the HTTP `DELETE` verb, as denoted by the `[HttpDelete]` attribute.
* Requires that the `id` parameter's value is included in the URL segment after `pizza/`.
* Returns `IActionResult` because the `ActionResult` return type isn't known until runtime. The `NotFound` and `NoContent` methods return `NotFoundResult` and `NoContentResult` types, respectively.
* Queries the in-memory cache for a pizza that matches the provided `id` parameter.

Remember to save the *Controllers/PizzaController.cs* file before proceeding,

### Build and run the finished web API <a href="#build-and-run-the-finished-web-api" id="build-and-run-the-finished-web-api"></a>

Try to create a pizza as shown:

<figure><img src="/files/dS9ND7ZufZ2XDPR1ojfz" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/kus1fWeYLOgnVdAuYcVO" alt=""><figcaption></figcaption></figure>

{% hint style="info" %}
Note how the new pizza is shown in the response body and also a location Uri is created for pizza 3. This is required when clients want to do more with the new object!
{% endhint %}

You can also see the newly created pizza if you do a get request for showing all pizzas. Note that this has to be done before you stop the application since we don't have a backing database and we are reading from cache!

<figure><img src="/files/ac3R1OFIKXGds5WgXC89" alt=""><figcaption></figcaption></figure>

Similarly, you can try editing and deleting a pizza!

### Videos for learning more <a href="#videos-for-learning-more" id="videos-for-learning-more"></a>

* [.NET 101](https://learn.microsoft.com/en-us/shows/NET-Core-101/?WT.mc_id=Educationaldotnet-c9-scottha)
* [ASP.NET Core Web API 101](https://learn.microsoft.com/en-us/shows/Beginners-Series-to-Web-APIs/)
* [ASP.NET Core 101](https://learn.microsoft.com/en-us/shows/ASPNET-Core-101/?WT.mc_id=Educationaspnet-c9-niner)


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://raviram.gitbook.io/webapi-module-1/create-pizza-api/implement-crud.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.