Delete Data - Entity Object Generator
Introduction
This article demonstrates an interesting and very useful concept in Entity Framework.
Question: What is entity object generator?
In simple terms "It is a template that enables generation of entity classes by creating text template files that customizes the entities".
Step 1: Create a new web application
![new-project-windows.jpg]()
Step 2: Adding a new entity data model framework:
![add-new-item.jpg]()
Step 3: Adding an entity object generator:
![add-code-generator.jpg]()
![entityobject-generator.jpg]()
Step 4: The complete code of WebForm1.aspx is as in the following:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="EntityObjectDeleteData.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" align="center">
<asp:Label ID="Label1" runat="server" Text="Delete Data - Entity Object Generator"
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 5: The complete code of WebForm1.aspx.cs is as in the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace EntityObjectDeleteData
{
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
{
int id = int.Parse(TextBox1.Text);
var query = (from r in objEntities.tblEmployee where r.EmpId == id select r).Single();
objEntities.DeleteObject(query);
objEntities.SaveChanges();
Label3.Text = "Data Deleted Successfully";
Label3.ForeColor = System.Drawing.Color.Green;
TextBox1.Text = string.Empty;
}
}
#region Instance MembersCompanyEntities objEntities = new CompanyEntities();
#endregion
}
}
Step 6: The output of the application is as in the following:
![delete-data.jpg]()
Step 7: The deleted data output of the application is as in the following:
![delete-data-succesfully.jpg]()
Update Data - Entity Object Generator
Question: What is entity object generator?
In simple terms "It is a template that enables generation of entity classes by creating text template files that customizes the entities".
Step 1: Create a new web application
![new-project1.jpg]()
Step 2: Adding a new entity data model framework:
![add-new-items1.jpg]()
Step 3: Adding an entity object generator:
![add-code-generator.jpg]()
![entityobject-generator1.jpg]()
Step 4: The complete code of WebForm1.aspx is as in the following:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="EntityObjectUpdateData.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 - Entity Object Generator"
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 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 First Name" 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 Last Name" 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="Button1" runat="server" Text="Update" Font-Names="Verdana" Width="213px"
BackColor="Orange" Font-Bold="True" OnClick="Button1_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 5: The complete code of WebForm1.aspx.cs is as in the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace EntityObjectUpdateData
{
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) || string.IsNullOrEmpty(TextBox2.Text) ||string.IsNullOrEmpty(TextBox3.Text) || string.IsNullOrEmpty(TextBox4.Text))
{
Label5.Text = "Please Enter Some Data";
Label5.ForeColor = System.Drawing.Color.Red;
}
else
{
var id1 = Convert.ToInt32(TextBox4.Text);
var objEmployee = objEntities.tblEmployee.Where(a => a.EmpId == id1).FirstOrDefault();
objEmployee.FirstName = TextBox1.Text;objEmployee.LastName = TextBox2.Text;
objEmployee.Age = int.Parse(TextBox3.Text);
objEntities.SaveChanges();
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;
}
}
#region Instance MembersCompanyEntities objEntities = new CompanyEntities();
#endregion
}
}
Step 6: The output of the application is as in the following:
![update-data.jpg]()
Step 7: The updated data output of the application is as in the following:
![update-data-successfully.jpg]()
I hope this article was useful for you.