Lets Play Around With Proxy Design Pattern

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 Proxy Pattern?

In simple terms "In this pattern, an interface actually points out to the specific implemented class to perform a specific operation".

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="ProxyPatternApplication._Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

</head>

<body>

<div>

Proxy Pattern - Design Patterns</h1>

<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>

<asp:Button ID="Button1" runat="server" Text="Addition" Width="165px" Font-Names="Verdana" BackColor="Orange" OnClick="Button1_Click" />

</td>

</tr>

<tr>

<asp:Button ID="Button2" runat="server" Text="Subtraction" Width="165px" Font-Names="Verdana" BackColor="Orange" OnClick="Button2_Click" />

</td>

</tr>

<tr>

<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>

<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 ProxyPatternApplication

{

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 ProxyPatternApplication

{

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 ProxyPatternApplication

{

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 ProxyPatternApplication

{

public interface IDiv

{

double Div(double a, double b);

}

Step 6: The complete code of AdditionClass.cs looks like this:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

namespace ProxyPatternApplication

{

public class AdditionClass : IAdd

{

public double Add(double a, double b)

{

return a + b;

}

Step 7: The complete code of SubtractionClass.cs looks like this:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

namespace ProxyPatternApplication

{

public class SubtractionClass : ISub

{

public double Sub(double a, double b)

{

return a - b;

}

Step 8: The complete code of MultiplicationClass.cs looks like this:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

namespace ProxyPatternApplication

{

public class MultiplicationClass : IMul

{

public double Mul(double a, double b)

{

return a * b;

}

Step 9: The complete code of DivisionClass.cs looks like this:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

namespace ProxyPatternApplication

{

public class DivisionClass : IDiv

{

public double Div(double a, double b)

{ return a / b;

}

Step 10: 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 ProxyPatternApplication

{

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

}

public void Button1_Click(object sender, EventArgs e)

{

if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))

{

lblResult.Text = "Please Enter Some Values";

}

else

{

lblResult.Text = "Addition Result of " + TextBox1.Text + " and " + TextBox2.Text + " is: <b>" + objAdd.Add(Convert.ToDouble(TextBox1.Text), Convert.ToDouble(TextBox2.Text)).ToString() + "</b>"; TextBox1.Text = ""; TextBox2.Text = "";

}

public void Button2_Click(object sender, EventArgs e)

{

if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))

{

lblResult.Text = "Please Enter Some Values";

}

else

{

lblResult.Text = "Subtraction Result of " + TextBox1.Text + " and " + TextBox2.Text + " is: <b>" + objSub.Sub(Convert.ToDouble(TextBox1.Text), Convert.ToDouble(TextBox2.Text)).ToString() + "</b>"; TextBox1.Text = ""; TextBox2.Text = "";

}

public void Button3_Click(object sender, EventArgs e)

{

if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))

{

lblResult.Text = "Please Enter Some Values";

}

else

{

lblResult.Text = "Multiplication Result of " + TextBox1.Text + " and " + TextBox2.Text + " is: <b>" + objMul.Mul(Convert.ToDouble(TextBox1.Text), Convert.ToDouble(TextBox2.Text)).ToString() + "</b>"; TextBox1.Text = ""; TextBox2.Text = "";

}

public void Button4_Click(object sender, EventArgs e)

{

if (string.IsNullOrEmpty(TextBox1.Text) || string.IsNullOrEmpty(TextBox2.Text))

{

lblResult.Text = "Please Enter Some Values";

}

else

{

lblResult.Text = "Division Result of " + TextBox1.Text + " and " + TextBox2.Text + " is: <b>" + objDiv.Div(Convert.ToDouble(TextBox1.Text), Convert.ToDouble(TextBox2.Text)).ToString() + "</b>"; TextBox1.Text = ""; TextBox2.Text = "";

}

#region Instance VariblesIAdd objAdd = new AdditionClass();ISub objSub = new SubtractionClass();IMul objMul = new MultiplicationClass();IDiv objDiv = new DivisionClass();#endregion

}

Step 11: The output of the application looks like this:

Step 12: The output of the nothing entered application looks like this:

Step 13: The output of the addition operation application looks like this:

I hope this article is useful for you. I look forward to your comments and feedback.