Introduction
Today, in this article let's play around with one of the interesting and most useful concepts in EDM Framework.
Delete Data with Entity State (Deleted) via EDF Framework
Question: What is delete data with Entity State (Deleted) via EDM framework?
In simple terms "It provides flexibility to delete the data using entity state; deleted via EDM framework".
Step 1: Create a new web application
![Delete-Data-with-Entity-State1.png]()
Step 2: Set up a new EDM framework with reverse engineering to the project
![Delete-Data-with-Entity-State2.png]()
Step 3: The complete code of WebForm1.aspx looks like this:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="DeleteDataEntityStateDeletedApp.WebForm1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<style type="text/css">
.grid
{
margin-top: 50px;
}
</style>
<title></title>
</head>
<body>
<form id="form1" runat="server">
<center>
<div>
<table>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label1" runat="server" Text="Delete Data with Entity State (Deleted) via Entity Framework"
Font-Bold="true" Font-Size="Large" Font-Names="Verdana" ForeColor="Maroon"></asp:Label>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Please Enter Employee Id" ForeColor="Brown"
Font-Bold="true" Font-Size="Medium" Font-Names="Verdana"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Button ID="Button1" runat="server" Text="Delete Data" Font-Names="Verdana" Width="213px"
BackColor="Orange" Font-Bold="True" OnClick="Button1_Click" />
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label3" runat="server" Font-Bold="true" Font-Size="Medium" Font-Names="Verdana"></asp:Label>
</td>
</tr>
</table>
</div>
</center>
</form>
</body>
</html>
Step 4: The complete code of WebForm1.aspx.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DeleteDataEntityStateDeletedApp.Models;
using System.Data;
namespace DeleteDataEntityStateDeletedApp
{
public partial class WebForm1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text))
{
Label3.Text = "Please Enter Some Values";
Label3.ForeColor = System.Drawing.Color.Red;
}
else
{
tblEmployee deleteQuery;
int empId = Convert.ToInt32(TextBox1.Text);
using (var objContext = new CompanyContext())
{
deleteQuery = (from r in objContext.tblEmployeeswhere r.EmpId == empIdselect r).Single();
}
eleteEmployee(deleteQuery);
Label3.Text = "Data Deleted Successfully";
Label3.ForeColor = System.Drawing.Color.Green;
TextBox1.Text = string.Empty;
}
}
private void deleteEmployee(tblEmployee employee)
{
using (var objContext = new CompanyContext())
{
objContext.Entry(employee).State = EntityState.Deleted;
objContext.SaveChanges();
}
}
}
}
Step 5: The output of the application looks like this:
![Delete-Data-with-Entity-State3.png]()
Step 6: The deleted data output of the application looks like this:
![Delete-Data-with-Entity-State4.png]()
Update Data with Entity State (Modified) via EDF Framework
Question: What is update data with Entity State (Modified) via EDM framework?
In simple terms "It provides flexibility to update the data using entity state; modified via EDM framework".
Step 1: Create a new web application
![Update-Data-with-Entity-State1.png]()
Step 2: Set up a new EDM framework with entity status to the project
![Update-Data-with-Entity-State2.png]()
Step 3: The complete code of WebForm1.aspx looks like this:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="UpdateDataEntityStateModifiedApp.WebForm1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<center>
<div>
<table>
<tr>
<td colspan="2">
<asp:Label ID="Label1" runat="server" Text="Update Data with Entity State - (Modified) via EDM Framework"
Font-Bold="true" Font-Size="Large" Font-Names="Verdana" ForeColor="Maroon"></asp:Label>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label6" runat="server" Text="Please Enter Employee Id" Font-Size="Large"
Font-Names="Verdana" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Please Enter FirstName" Font-Size="Large"
Font-Names="Verdana" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label3" runat="server" Text="Please Enter LastName" Font-Size="Large"
Font-Names="Verdana" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label4" runat="server" Text="Please Enter Age" Font-Size="Large" Font-Names="Verdana"
Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Button ID="Button2" runat="server" Text="Update Data" Font-Names="Verdana" Width="166px"
BackColor="Orange" Font-Bold="True" OnClick="Button2_Click" />
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label5" runat="server" Font-Bold="true" Font-Names="Verdana" ForeColor="Maroon"></asp:Label>
</td>
</tr>
</table>
</div>
</center>
</form>
</body>
</html>
Step 4: The complete code of WebForm1.aspx.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using UpdateDataEntityStateModifiedApp.Models;
namespace UpdateDataEntityStateModifiedApp
{
public partial class WebForm1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button2_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text) || string.IsNullOrEmpty(TextBox3.Text) || string.IsNullOrEmpty(TextBox4.Text))
{
Label5.Text = "Please Enter Some Values";
Label5.ForeColor = System.Drawing.Color.Red;
}
else
{
tblEmployee employeeQuery;
using (var dbContext = new CompanyContext())
{
int empId = Convert.ToInt32(TextBox4.Text);
employeeQuery = (from r in dbContext.tblEmployees where r.EmpId == empId select r).Single();
}
employeeQuery.FirstName = TextBox1.Text;
employeeQuery.LastName = TextBox2.Text;
employeeQuery.Age = int.Parse(TextBox3.Text);
updateEmployee(employeeQuery);
Label5.Text = "Data Updated Successfully";
Label5.ForeColor = System.Drawing.Color.Green;
TextBox1.Text = string.Empty;
TextBox2.Text = string.Empty;
TextBox3.Text = string.Empty;
TextBox4.Text = string.Empty;
}
}
private void updateEmployee(tblEmployee tblEmployee)
{
using (var objContext = new CompanyContext())
{
objContext.Entry(tblEmployee).State = System.Data.EntityState.Modified;
objContext.SaveChanges();
}
}
}
}
Step 5: The output of the application looks like this:
![Update-Data-with-Entity-State3.png]()
Step 6: The modified data output of the application looks like this:
![Update-Data-with-Entity-State4.png]()