C#

Bardy85 wrote:

Well it is right but proberly doesn't follow best practises.

I are Troll

public class Employee
{
}

public class EmployeeList : List<Employee>
{
    public EmployeeList(bool populateNow)
    {
        if (populateNow)
        {
            GetFromDatabase();
        }
    }

    public void GetFromDatabase()
    {
        // do whatever you need to do to retrieve the employees from the database
        this.AddRange(blah blah);
    }
}

EmployeeList employees = new EmployeeList(true);

public static class Globals
{
    public static EmployeeList Employees { get; private set; }

    static Globals()
    {
        Employees = new EmployeeList(true);
    }
}

public struct MyStruct
{
    public byte a;
    public int b;
}

ArjenGroeneveld wrote:

I studied the BindingSource control, but I cannot find an 'IsDirty' property as well no event related to this.

ArjenGroeneveld wrote:

CONCREET: I like to customize the BindingSource by simply adding an "IsDirty" property and an "IsDirtychanged" event. Will this be an easy one????

I are Troll

ArjenGroeneveld wrote:

Okay, Can you help me with the code?

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

namespace Example
{
	public class MyBinding : Binding
	{
		bool _isDirty;
		public bool IsDirty
		{
			get
			{
				return _isDirty;
			}
			set
			{
				if (_isDirty != value)
					_isDirty = value;
			}
		}
		
		public MyBinding(string propertyName, object DataSource, string dataMember)
			:base(propertyName, DataSource, dataMember)
		{
			// more stuff!!
		}
	}
	
	public class Form1 : System.Windows.Forms.Form 
	{
		static void Main() 
		{
			Application.Run(new Form1());
		}
		
		private TextBox textBox1;
		private ListBox listBox1;
		private MyBinding myBinding;
		
		public Form1() 
		{
			InitializeComponent();
		}
	
		private void InitializeComponent()
		{
			SuspendLayout();
			listBox1 = new ListBox();
			textBox1 = new TextBox();
	
			textBox1.Location = new Point(16, 68);
			textBox1.Size = new Size(144, 20);		
			
			listBox1.Location = new Point(16, 8);
			listBox1.Size = new Size(144, 50);

			ClientSize = new Size(176, 100);
			Controls.Add(textBox1);
			Controls.Add(listBox1);
				
			Name = "Form1";
			Text = "Form1";
			Load += new EventHandler(Form1_Load);
			ResumeLayout(false);
		}		
		
		private void Form1_Load(object sender, System.EventArgs e) 
		{
			DataTable dt = new DataTable("employee");
			dt.Columns.Add("firstname");
			dt.Columns.Add("lastname");
			dt.Rows.Add("john", "doe");
			dt.Rows.Add("johnny", "walker");		
			
			listBox1.DataSource = dt;
			listBox1.DisplayMember = "firstname";

			myBinding = new MyBinding("Text", listBox1.DataSource, "lastname");
			textBox1.DataBindings.Add(myBinding);
		}
	}
}

I are Troll

protected override void OnCurrentItemChanged (System.EventArgs e)
{
	base.OnCurrentItemChanged (e);
	if (IsDirty == false)
		IsDirty = true;
}

I are Troll