C#

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        Session.Add("Test", "Testing session pass");
    }
}

public partial class FormPage : System.Web.UI.Page
{

    protected void Page_Load(object sender, EventArgs e)
    {        
        Response.Write(Session["Test"].ToString());            //<-- Get error on this line
    }
}

ConfigurationManager.AppSettings["MySettingName"]

Session["MySettingName"]

AnyDigitButton_Clicked(object sender, EventArgs e) {
    Button btn=sender as Button;
    number=10*number+(int)btn.Tag;
}

nstk wrote:

Maybe by putting them inside a groupBox?

nstk wrote:

Where does the Method 'AnyDigitButton_Clicked' come from?

int number = 0;

number = Convert.ToInt32(btn.Tag);

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows.Forms;

public class CalculatorDigitButton : Button
{
    public const int MaxValue = 9;
    public const int MinValue = 0;

    public CalculatorDigitButton()
    {
        base.Text = "0";
    }

    private int value;

    [Browsable(false)]
    public new string Text
    {
        get { return base.Text; }
        set { }
    }
    public int Value
    {
        get { return value; }
        set
        {
            if (value < MinValue || value > MaxValue)
                throw new ArgumentOutOfRangeException(
                    "value",
                    string.Format("Value must be between {0} and {1}",
                        MinValue, MaxValue));
            this.value = value;
            base.Text = value.ToString();
        }
    }
}

public enum CalculatorFunction
{
    Add,
    Subtract,
    Multiply,
    Divide
}

public class CalculatorFunctionButton : Button
{
    private static readonly List<string> FunctionText = new List<string>(4){
        "+", "-", "*", "/" };

    private CalculatorFunction function;

    public CalculatorFunctionButton()
    {
        base.Text = FunctionText[0];
    }

    public CalculatorFunction Function
    {
        get { return function; }
        set
        {
            if (!Enum.IsDefined(typeof(CalculatorFunction), value))
                throw new ArgumentException(
                    "Function must be a defined value", "Function");
            function = value;
            base.Text = FunctionText[(int)function];
        }
    }
    [Browsable(false)]
    public new string Text
    {
        get { return base.Text; }
        set { }
    }
}

// Assign each digit button's click event to this handler
private void CalculatorDigitButtonClick(object sender, EventArgs e)
{
    CalculatorDigitButton calculatorDigitButton = sender as CalculatorDigitButton;
    if (calculatorDigitButton != null)
    {
        // Do your thing, value is in calculatorDigitButton.Value
    }
}
// Assign each function button's click event to this handler
private void CalculatorFunctionButtonClick(object sender, EventArgs e)
{
    CalculatorFunctionButton calculatorFunctionButton = sender as CalculatorFunctionButton;
    if (calculatorFunctionButton != null)
    {
        // Do your thing, function is in calculatorFunctionButton.Function
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        System.Timers.Timer greentimer;
        System.Timers.Timer redtimer;

        public Form1()
        {
            InitializeComponent();
            greentimer = System.Timers.Timer(3000);
            greentimer.Elapsed += new System.Timers.ElapsedEventHandler(greenTimer_Elapsed);
            greentimer.Start();

            redtimer = System.Timers.Timer(3000);
           redtimer.Elapsed += new System.Timers.ElapsedEventHandler(redTimer_Elapsed);
            redtimer.Start();

        }
        void redTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
             button1.Invoke(new Action(() => button1.BackColor=Color.Green));

        }
        private void button1_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        [STAThread]
        static void Main()
        {
            
            Application.Run( Form1);
        }
    }
}

greentimer = new System.Timers.Timer(3000);
...
redtimer = new System.Timers.Timer(3000);