Introduction
Today, in this article let's play around with one of the interesting and most useful concepts of design patterns, which will be hosted in a web app.
Question: What is a Factory Pattern ?
In simple terms "Creates an object without exposing implementation logic to the client".
I think we are now good to go to implement this wonderful concept.
Step 1: The complete code of Default.aspx looks like this:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="FactoryPatternApplication._Default" %>
<! 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 runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h1 style="text-align:center; font-family:Verdana; font-size:large; color:Maroon">Factory Pattern - Design Patterns</h1>
<center>
<table>
<tr>
<td>
<asp:Label ID="Label1" runat="server" Text="Please Enter First Number" Font-Size="Small" Font-Bold="true" Font-Italic="true" Font-Names="Verdana"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Please Enter Second Number" Font-Size="Small" Font-Bold="true" Font-Italic="true" Font-Names="Verdana"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="Button1" runat="server" Text="Addition" Width="165px"Font-Names="Verdana" BackColor="Orange" onclick="Button1_Click" />
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="Button2" runat="server" Text="Subtraction" Width="165px"Font-Names="Verdana" BackColor="Orange" onclick="Button2_Click" />
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="Button3" runat="server" Text="Multiplication" Width="165px"Font-Names="Verdana" BackColor="Orange" onclick="Button3_Click" />
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="Button4" runat="server" Text="Division" Width="165px"Font-Names="Verdana" BackColor="Orange" onclick="Button4_Click" />
</td>
</tr>
</table>
<table>
<tr>
<td colspan="2">
<asp:Label ID="lblResult" runat="server" Font-Names="Verdana" ForeColor="Brown"></asp:Label>
</td>
</tr>
</table>
</center>
</div>
</form>
</body>
</html>
Step 2: The complete code of IAdd.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FactoryPatternApplication
{
public interface IAdd
{
double Add(double a, double b);
}
}
Step 3: The complete code of ISub.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FactoryPatternApplication
{
public interface ISub
{
double Sub(double a, double b);
}
}
Step 4: The complete code of IMul.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FactoryPatternApplication
{
public interface IMul
{
double Mul(double a, double b);
}
}
Step 5: The complete code of IDiv.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FactoryPatternApplication
{
public interface IDiv
{
double Div(double a, double b);
}
}
Step 6: The complete code of Addition.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FactoryPatternApplication
{
public class AdditionClass : IAdd
{
public double Add(double a, double b)
{
return a + b;
}
}
}
Step 7: The complete code of Subtraction.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FactoryPatternApplication
{
public class SubtractionClass : ISub
{
public double Sub(double a, double b)
{
return a - b;
}
}
}
Step 8: The complete code of Multiplication.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FactoryPatternApplication
{
public class MultiplicationClass : IMul
{
public double Mul(double a, double b)
{
return a * b;
}
}
}
Step 9: The complete code of Division.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FactoryPatternApplication
{
public class DivisionClass : IDiv
{
public double Div(double a, double b)
{
return a / b;
}
}
}
Step 10: The complete code of ArthmeticFactory.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI.WebControls;
namespace FactoryPatternApplication
{
public class ArthmeticFactory
{
public IAdd getAdd(string a)
{
if (a == "Addition"){return new AdditionClass();
}
elsereturn null;
}
public ISub getSub(string a)
{
if (a == "Subtraction")
{
return new SubtractionClass();
}
elsereturn null;
}
public IMul getMul(string a){if (a == "Multiplication")
{
return new MultiplicationClass();
}
elsereturn null;
}
public IDiv getDiv(string a)
{
if (a == "Division")
{
return new DivisionClass();
}
elsereturn null;
}
}
}
Step 11: The complete code of Default.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;namespace FactoryPatternApplication
{
public partial class _Default : 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))
{
lblResult.Text = "Please Enter Some Values";
}
else
{
var a = Button1.Text;IAdd obj_Add = objFactory.getAdd(a);
lblResult.Text = "Addition Result of " + TextBox1.Text + " and " + TextBox2.Text + " is : <b>" + obj_Add.Add
(Convert.ToDouble(TextBox1.Text), Convert.ToDouble(TextBox2.Text)) + "</b>";TextBox1.Text = "";
TextBox2.Text = "";}}protected void Button2_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))
{
lblResult.Text = "Please Enter Some Values";
}
else
{
var a = Button2.Text;ISub obj_Sub = objFactory.getSub(a);
lblResult.Text = "Subtraction Result of " + TextBox1.Text + " and " + TextBox2.Text + " is : <b>" +
obj_Sub.Sub(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b>";TextBox1.Text = "";
TextBox2.Text = "";
}
}
protected void Button3_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))
{
lblResult.Text = "Please Enter Some Values";
}
else
{
var a = Button3.Text;IMul obj_Mul = objFactory.getMul(a);
lblResult.Text = "Multiplication Result of " + TextBox1.Text + " and " + TextBox2.Text + " is : <b>" + obj_Mul.Mul
(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b>";TextBox1.Text = "";TextBox2.Text = "";
}
}
protected void Button4_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))
{
lblResult.Text = "Please Enter Some Values";
}
else
{
var a = Button4.Text;IDiv obj_Div = objFactory.getDiv(a);lblResult.Text = "Division Result of " +
TextBox1.Text + " and " + TextBox2.Text + " is : <b>" + obj_Div.Div
(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b>";TextBox1.Text = "";TextBox2.Text = "";
}
}
#region Instance MembersArthmeticFactory objFactory = new ArthmeticFactory();#endregion
}
}
Step 12: The output of the application looks like this:
![Output1.png]()
Step 13: The output of the nothing entered application looks like this:
![Output2.png]()
Step 14: The output of the addition operation application looks like this:
![Output3.png]()
Step 15: The output of the division operation application looks like this:
![Output4.png]()