AspNetCore.Docs/aspnetcore/includes/webApi/end.md

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## Implement the other CRUD operations
We'll add `Create`, `Update`, and `Delete` methods to the controller. These are variations on a theme, so I'll just show the code and highlight the main differences. Build the project after adding or changing code.
### Create
[!code-csharp[Main](../../tutorials/first-web-api/sample/TodoApi/Controllers/TodoController.cs?name=snippet_Create)]
2017-09-20 00:47:36 +08:00
This is an HTTP POST method, indicated by the [`[HttpPost]`](/aspnet/core/api/microsoft.aspnetcore.mvc.httppostattribute) attribute. The [`[FromBody]`](/aspnet/core/api/microsoft.aspnetcore.mvc.frombodyattribute) attribute tells MVC to get the value of the to-do item from the body of the HTTP request.
The `CreatedAtRoute` method returns a 201 response, which is the standard response for an HTTP POST method that creates a new resource on the server. `CreatedAtRoute` also adds a Location header to the response. The Location header specifies the URI of the newly created to-do item. See [10.2.2 201 Created](http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html).
### Use Postman to send a Create request
![Postman console](../../tutorials/first-web-api/_static/pmc.png)
* Set the HTTP method to `POST`
* Select the **Body** radio button
* Select the **raw** radio button
* Set the type to JSON
* In the key-value editor, enter a Todo item such as
```json
{
"name":"walk dog",
"isComplete":true
}
```
* Select **Send**
* Select the Headers tab in the lower pane and copy the **Location** header:
![Headers tab of the Postman console](../../tutorials/first-web-api/_static/pmget.png)
You can use the Location header URI to access the resource you just created. Recall the `GetById` method created the `"GetTodo"` named route:
```csharp
[HttpGet("{id}", Name = "GetTodo")]
public IActionResult GetById(long id)
```
### Update
[!code-csharp[Main](../../tutorials/first-web-api/sample/TodoApi/Controllers/TodoController.cs?name=snippet_Update)]
`Update` is similar to `Create`, but uses HTTP PUT. The response is [204 (No Content)](http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html). According to the HTTP spec, a PUT request requires the client to send the entire updated entity, not just the deltas. To support partial updates, use HTTP PATCH.
![Postman console showing 204 (No Content) response](../../tutorials/first-web-api/_static/pmcput.png)
### Delete
[!code-csharp[Main](../../tutorials/first-web-api/sample/TodoApi/Controllers/TodoController.cs?name=snippet_Delete)]
The response is [204 (No Content)](http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html).
![Postman console showing 204 (No Content) response](../../tutorials/first-web-api/_static/pmd.png)