Introduction
Today, in this article let's play around with an interesting and one of the most useful concepts of design pattern, which will be hosted in a web app.
Question: What is Facade Pattern?
In simple terms "It acts as a single set of unified wrappers for multiple complex classes, it wraps a bunch of complex classes into a single unique facade pattern class. By doing this we can minimize complexity faced when code keeps growing and growing. It provides a more sophisticated look when even looked at class diagram and easy understandability ".
The diagrammatic representation of the Facade Pattern - Design Pattern for this application looks like this:
![Image1.png]()
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="FacadePatternApplication._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 id="Head1" 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">
Facade 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 / Subtraction" Width="165px"
Font-Names="Verdana" BackColor="Orange" OnClick="Button1_Click" />
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="Button2" runat="server" Text="Multiply / Divide" Width="165px" Font-Names="Verdana"
BackColor="Orange" OnClick="Button2_Click" />
</td>
</tr>
</table>
<table>
<tr>
<td colspan="2">
<asp:Label ID="lblResult" runat="server" Font-Names="Verdana" ForeColor="Brown"></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:Label ID="lblResult1" runat="server" Font-Names="Verdana" ForeColor="Brown"></asp:Label>
</td>
</tr>
</table>
</center>
</div>
</form>
</body>
</html>
Step 2: The complete code of PartialAddClass.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FacadePatternApplication
{
public class PartialAddClass
{
public double Add(double a, double b)
{
return a + b;
}
}
}
Step 3: The complete code of PartialSubClass.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FacadePatternApplication
{
public class PartialSubClass
{
public double Sub(double a, double b)
{
return a - b;
}
}
}
Step 4: The complete code of PartialMulClass.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FacadePatternApplication
{
public class PartialMulClass
{
public double Mul(double a, double b)
{
return a * b;
}
}
}
Step 5: The complete code of PartialDivClass.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace FacadePatternApplication
{
public class PartialDivClass
{
public double Div(double a, double b)
{
return a / b;
}
}
}
Step 6: 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;
using WebApplication3;
namespace FacadePatternApplication
{
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"; lblResult1.Text = "";
}
else
{
AddSub(); 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"; lblResult1.Text = "";
}
else
{
MulDiv(); TextBox1.Text = ""; TextBox2.Text = "";
}
}
public void AddSub()
{
lblResult.Text= "Addition Result is <b>"+objAdd.Add(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text))+"</b></br>";
lblResult1.Text = "Subtraction Result is <b>" + objSub.Sub(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b></br>";
}
public void MulDiv()
{
lblResult.Text = "Multiplication Result is <b>" + objMul.Mul(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b></br>";
lblResult1.Text = "Division Result is <b>" + objDiv.Div(Convert.ToDouble(TextBox1.Text),
Convert.ToDouble(TextBox2.Text)) + "</b></br>";
}
#region Instance Variables PartialAddClass objAdd = new PartialAddClass();
PartialSubClass objSub = new PartialSubClass();
PartialMulClass objMul = new PartialMulClass();
PartialDivClass objDiv = new PartialDivClass();
#endregion
}
}
Step 7: The output of the application looks like this:
![Output1.png]()
Step 8: The output of the nothing entered application looks like this:
![Output2.png]()
Step 9: The output of the addition/subtraction operation application looks like this:
![Output3.png]()
![Output4.png]()
Step 10: The output of the multiplication/division operation application looks like this:
![Output5.png]()
I hope this article is useful for you. I look forward for your comments and feedback. Thanks Vijay Prativadi