Update control when property haschanged

Hi,

I finally found how to update the render of my custom control when one of its property value changed.

However, i would like to know if there is not another way, because i'm afraid about memory usage or leak.

The following code is only a change color property update, but it is easy to adapt it to other properties.
However, i'm scared about the custom control constructor. Every time i must add/link there an eventhandler... is it a must or does it exist another solution ?

thanks a lot,

Al.

---------------------
Here is my custom control class code :
namespace MyComponent
{
public partial class Frame : UserControl
{
#region Event Handler

private EventHandler HandlerColorChanged;

#endregion

public Frame()
{
InitializeComponent();
HandlerColorChanged = new EventHandler(OnGridLinePropertyChanged);
this.m_GridLines.ColorChanged += HandlerColorChanged;
}

private CGridLine m_GridLines= new CGridLine();

[Category("Appearance")]
[Browsable(true)]

[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
[Description("Setup Style, Type and Color of gridlines to draw.")]
[TypeConverter(typeof(CGridLineConverter))]
public CGridLine GridLines
{
get
{
return this.m_GridLines;
}
set
{
this.m_GridLines = value;
if (HandlerColorChanged != null)
{
this.m_GridLines.ColorChanged -= this.HandlerColorChanged;
}
this.HandlerColorChanged = new EventHandler(OnGridLinePropertyChanged);
this.m_GridLines.ColorChanged += this.HandlerColorChanged;
}
}

protected override void OnPaint(PaintEventArgs e)
{
if (this.m_GridLines.Lines != GridLine.None)
{
Pen myPen = new Pen(this.m_GridLines.Color);
e.Graphics.DrawRectangle(myPen, new Rectangle(0,0,this.Width-1,this.Height-1));
}
}

private void OnGridLinePropertyChanged(object Sender, EventArgs e)
{
// redraw the control
Invalidate();
}
}
}

and my GridClass code :

namespace MyComponent
{
/// <summary>
/// Specifies how a Table draws grid lines between its rows and columns
/// </summary>
public enum GridLine
{
/// <summary>
/// No grid lines are drawn
/// </summary>
None = 0,

/// <summary>
/// Grid lines are only drawn between columns
/// </summary>
Columns = 1,

/// <summary>
/// Grid lines are only drawn between rows
/// </summary>
Rows = 2,

/// <summary>
/// Grid lines are drawn between rows and columns
/// </summary>
All = 3
}

/// <summary>
/// Specifies the style of the lines drawn when a Table draws its grid lines
/// </summary>
public enum GridLineStyle
{
/// <summary>
/// Specifies a solid line
/// </summary>
Solid = 0,

/// <summary>
/// Specifies a line consisting of dashes
/// </summary>
Dash = 1,

/// <summary>
/// Specifies a line consisting of dots
/// </summary>
Dot = 2,

/// <summary>
/// Specifies a line consisting of a repeating pattern of dash-dot
/// </summary>
DashDot = 3,

/// <summary>
/// Specifies a line consisting of a repeating pattern of dash-dot-dot
/// </summary>
DashDotDot = 4
}

public class CGridLine
{

#region Event Handler

public event EventHandler ColorChanged;

#endregion

#region Class Data

private GridLine m_GridLines;
private GridLineStyle m_GridLinesStyle;
private Color m_GridLinesColor;

#endregion

#region Constructor

public CGridLine()
{
this.m_GridLines = GridLine.None;
this.m_GridLinesColor = System.Drawing.SystemColors.ActiveBorder;
this.m_GridLinesStyle = GridLineStyle.Solid;
}

public CGridLine(GridLine LineType, GridLineStyle LineStyle, Color LineColor)
{
this.m_GridLines = LineType;
this.m_GridLinesColor = LineColor;
this.m_GridLinesStyle = LineStyle;
}
#endregion

#region Properties

/// <summary>
/// Style of the GridLines
/// </summary>
///
[RefreshProperties(RefreshProperties.Repaint)]
[NotifyParentProperty(true)]
[DefaultValue(typeof(GridLineStyle), "Solid")]
public GridLineStyle Style
{
get
{
return this.m_GridLinesStyle;
}
set
{
this.m_GridLinesStyle = value;
//this.OnColorChanged(EventArgs.Empty);
}
}

/// <summary>
/// Types of GridLines
/// </summary>
[RefreshProperties(RefreshProperties.Repaint)]
[NotifyParentProperty(true)]
[DefaultValue(typeof(GridLine), "None")]
public GridLine Lines
{
get
{
return this.m_GridLines;
}
set
{
this.m_GridLines = value;
//this.OnPropertyChanged(EventArgs.Empty);
}
}

/// <summary>
/// Color of the GridLine
/// </summary>
[RefreshProperties(RefreshProperties.Repaint)]
[NotifyParentProperty(true)]
[DefaultValue(typeof(Color), "ActiveBorder")]
public Color Color
{
get
{
return this.m_GridLinesColor;
}
set
{
if (this.m_GridLinesColor != value)
{
this.m_GridLinesColor = value;
OnColorChanged(EventArgs.Empty);
}
}
}

#endregion

#region Event

private void OnColorChanged(EventArgs e)
{
// event has been raised
if (ColorChanged != null)
{
ColorChanged(this, e);
}
}

#endregion

}

public class CGridLineConverter : ExpandableObjectConverter
{
...
}
}
.

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