In this article I describe how to determine if a number is a Perfect Number. But first let us understand what a Perfect Number is.

Perfect Number

A number is called a Perfect Number when the sum of its perfect divisors (except itself) are equal to a given number. In other words, a Perfect Number is a number that equals the sum of its factors.

Example: Number 6 = 1+2+3.

Use the following procedure to create a Perfect Number app in Windows Store.

Step 1

First of all you have to create a New Window Store Application.

new-windows-store-app.jpg

Step 2

Write XAML code for "Mainpage.Xaml" that is available in Solution Explorer; see:

<Page

x:Class="armstrong_app.MainPage"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:local="using:armstrong_app"

xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

mc:Ignorable="d">

<Grid Background="Blue">

<Grid.RowDefinitions>

<RowDefinition Height="38*"/>

<RowDefinition Height="23*"/>

<RowDefinition Height="31*"/>

<RowDefinition Height="32*"/>

<RowDefinition Height="35*"/>

<RowDefinition Height="609*"/>

</Grid.RowDefinitions>

<Grid.ColumnDefinitions>

<ColumnDefinition Width="161*"/>

<ColumnDefinition Width="303*"/>

<ColumnDefinition Width="902*"/>

</Grid.ColumnDefinitions>

<TextBlock Text="Check Number is Perfect Number or not" FontFamily="Arial" FontSize="14" FontWeight="ExtraBold" Foreground="Red" Grid.Column="1" Grid.Row="1" Grid.ColumnSpan="2"></TextBlock>

<TextBlock Text="Enter Number:" FontFamily="Arial" FontSize="15" FontWeight="ExtraBold" Foreground="Red" Grid.Column="1" Grid.Row="2"></TextBlock>

<TextBox x:Name="Textbox1" Width="150" Height="32" VerticalAlignment="Top" Grid.Column="2" Grid.Row="2" HorizontalAlignment="Left" Grid.RowSpan="2" />

<TextBlock Text="Number is:" FontFamily="Arial" FontSize="15" FontWeight="ExtraBold" Foreground="Red" Grid.Column="1" Grid.Row="3"></TextBlock>

<TextBlock x:Name="text2" FontFamily="Arial" FontSize="15" FontWeight="ExtraBold" Foreground="Red" Grid.Column="2" Grid.Row="3"></TextBlock>

<Button x:Name="button1" Content="Click" Grid.Row="3" Grid.Column="2" Background="Yellow" Foreground="Red" Width="103" Height="34" FontSize="15" Margin="0,31,0,2" Grid.RowSpan="2" Click="button1_Click"/>

</Grid>

</Page>

Step 3

Now write C# code for the button within "Mainpage.Xaml.cs"; see:

using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using Windows.Foundation;

using Windows.Foundation.Collections;

using Windows.UI.Xaml;

using Windows.UI.Xaml.Controls;

using Windows.UI.Xaml.Controls.Primitives;

using Windows.UI.Xaml.Data;

using Windows.UI.Xaml.Input;

using Windows.UI.Xaml.Media;

using Windows.UI.Xaml.Navigation;

namespace Perfect_app
{
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
}
private void button1_Click(object sender, RoutedEventArgs e)
{
int num = Convert.ToInt32(Textbox1.Text);
int sum = 0;
for (int i = 1; i < num; i++)
{
if (num % i == 0)
{
sum = sum + i;
}
}
if (sum == num)
{
text2.Text =
"Perfect Number";
}
else
{
text2.Text =
"Not Perfect number";
}

}
}
}

Step 4

Run your App.

Run-the-applicatino.jpg

Step 5

Enter a number into the TextBox for determine if it is a Perfect Number.

output-perfect-number-app.jpg

not-perfect-number.jpg