In this article I will explain with an example, how to delete data from Database using Web API and Entity Framework in ASP.Net MVC Razor.
When the Delete Button is clicked, the DeleteCustomer Action method of the Web API is called using jQuery AJAX and the details of Customer are sent as JSON object.
Finally, a Customer object is sent to the View which indicates that the record was successfully deleted or not.
Note: For beginners in ASP.Net MVC and Web API, please refer my article: What is Web API, why to use it and how to use it in ASP.Net MVC for details about using and configuring Web API.
 
 
Database
I have made use of the following table Customers with the schema as follows. CustomerId is an Auto-Increment (Identity) column.
ASP.Net MVC: Delete data from Database using Web API and Entity Framework
 
I have already inserted few records in the table.
ASP.Net MVC: Delete data from Database using Web API and Entity Framework
 
Note: You can download the database table SQL by clicking the download link below.
          Download SQL file
 
 

Entity Framework Model
Once the Entity Framework is configured and connected to the database table, the Model will look as shown below.
Note: For beginners in ASP.Net MVC and Entity Framework, please refer my article ASP.Net MVC: Simple Entity Framework Tutorial with example. It covers all the information needed for connecting and configuring Entity Framework.
 
ASP.Net MVC: Delete data from Database using Web API and Entity Framework
 
 
Controller
The Controller consists of the following Action method.
Action method for handling GET operation
Inside this Action method, simply the View is returned.
public class HomeController : Controller
{
    // GET: Home
    public ActionResult Index()
    {
        return View();
    }
}
 
 
Web API Controller
The Web API Controller consists of the following Action method.
Action method for Deleting
Inside this Action method, the CustomerId value is received as parameter. The CustomerId value is used to reference the Customer record in the Customer Entities.
If the record is found, the Customer record is deleted from the Customers table and the Customer object is returned.
If the record is not found, then a NULL response is returned.
public class AjaxAPIController : ApiController
{
    [Route("api/AjaxAPI/DeleteCustomer")]
    [HttpPost]
    public Customer DeleteCustomer(Customer _customer)
    {
        using (CustomersEntities entities = new CustomersEntities())
        {
            Customer customer = (from c in entities.Customers
                                 where c.CustomerId == _customer.CustomerId
                                 select c).FirstOrDefault();
            if (customer != null)
            {
                entities.Customers.Remove(customer);
                entities.SaveChanges();
                return customer;
            }
        }
 
        return null;
    }
}
 
 
View
The View consists of a TextBox and a Button. The Button has been assigned with a jQuery Click event handler.
When the Delete button is clicked, the value of CustomerId are passed to the DeleteCustomer Action method using jQuery AJAX call.
Once the response is received, based on whether response is a Customer object or NULL object, appropriate message is displayed using JavaScript Alert Message Box.
@{
    Layout = null;
}
 
<!DOCTYPE html>
 
<html>
<head>
    <meta name="viewport" content="width=device-width"/>
    <title>Index</title>
</head>
<body>
    <table border="0" cellpadding="0" cellspacing="0">
        <tr>
            <td style="width: 150px">
                Customer Id:<br/>
                <input type="text" id="txtCustomerId" style="width:140px"/>
            </td>
            <td style="width: 200px">
                <br/>
                <input type="button" id="btnDelete" value="Delete"/>
            </td>
        </tr>
    </table>
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
    <script type="text/javascript" src="https://ajax.cdnjs.com/ajax/libs/json2/20110223/json2.js"></script>
    <script type="text/javascript">
        $("body").on("click", "#btnDelete", function () {
            if (confirm("Do you want to delete this Customer?")) {
                var _customer = {};
                _customer.CustomerId = $("#txtCustomerId").val();
                $.ajax({
                    type: "POST",
                    url: "/api/AjaxAPI/DeleteCustomer",
                    data: JSON.stringify(_customer),
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (customer) {
                        if (customer != null) {
                            alert("Deleted Customer: " + customer.Name);
                        } else {
                            alert("Customer record not found.");
                        }
                    }
                });
            }
        });
    </script>
</body>
</html>
 
 
Screenshot
ASP.Net MVC: Delete data from Database using Web API and Entity Framework
 
 
Downloads