colourbutton.cs

一个WINCE下用ado.net连接数据库的例子 作者:tanis

using System;
using System.Windows;
using System.Windows.Forms;
using System.Drawing;
#if NETCFDESIGNTIME
	using System.ComponentModel;
#endif

namespace ColourControls
{
	public class ColourButton : Control
	{
		/// <summary>
		/// Button that behaves the same as the standard button,
		/// but has properties for button colour and text colour
		/// for both normal state and pushed state.
		/// </summary>
#region Control Attributes
		//Remove two unwanted properties: BackColor and ForeColor
		#if NETCFDESIGNTIME
			[Browsable(false)]
			[EditorBrowsable(EditorBrowsableState.Never)]
		#endif
		public override Color BackColor
		{
			set
			{;}
			get
			{ return new Color(); }
		}
		#if NETCFDESIGNTIME
			[Browsable(false)]
			[EditorBrowsable(EditorBrowsableState.Never)]
		#endif
		public override Color ForeColor
		{
			set
			{;}
			get
			{ return new Color(); }
		}

		//Now add the properties for the four colours we do want:
		//	NormalBtnColour
		//	NormalTxtColour
		//	PushedBtnColour
		//	PushedTxtColour
		#if NETCFDESIGNTIME
			[Category("Appearance")]
			[DefaultValue(3)]
			[Description("The normal colour of the button.")]
		#endif
		public Color NormalBtnColour
		{
			set
			{
				m_NormalBtnColour = value;
				Invalidate();
			}
			get
			{
				return m_NormalBtnColour;
			}
		}
		#if NETCFDESIGNTIME
			[Category("Appearance")]
			[DefaultValue(3)]
			[Description("The normal colour of the button text.")]
		#endif
		public Color NormalTxtColour
		{
			set
			{
				m_NormalTxtColour = value;
				Invalidate();
			}
			get
			{
				return m_NormalTxtColour;
			}
		}
		#if NETCFDESIGNTIME
			[Category("Appearance")]
			[DefaultValue(3)]
			[Description("The colour of the button when clicked.")]
		#endif
		public Color PushedBtnColour
		{
			set
			{
				m_PushedBtnColour = value;
				Invalidate();
			}
			get
			{
				return m_PushedBtnColour;
			}
		}
		#if NETCFDESIGNTIME
			[Category("Appearance")]
			[DefaultValue(3)]
			[Description("The colour of the button text when clicked.")]
		#endif
		public Color PushedTxtColour
		{
			set
			{
				m_PushedTxtColour = value;
				Invalidate();
			}
			get
			{
				return m_PushedTxtColour;
			}
		}
#endregion

#region Attributes
		Color m_NormalBtnColour = Color.LightYellow;
		Color m_NormalTxtColour = Color.Blue;
		Color m_PushedBtnColour = Color.Blue;
		Color m_PushedTxtColour = Color.Yellow;

		public enum States 
		{ 
			Normal, 
			Pushed 
		}
		
		States m_state;
#endregion

	
#region Public Services
		public ColourButton()
		{
			m_state = States.Normal;
		}
#endregion

#region Protected/Private Services
		protected override void OnMouseDown(System.Windows.Forms.MouseEventArgs e) 
		{
			m_state = States.Pushed; 
			// button receives input focus
			Focus();  
			base.OnMouseDown(e); 
			Invalidate(); 
		} 
  
		protected override void OnMouseUp(System.Windows.Forms.MouseEventArgs e) 
		{
			m_state = States.Normal;
			base.OnMouseUp(e);
			Invalidate();
		}

		protected override void OnResize(EventArgs e)
		{
			base.OnResize(e);
			Invalidate();
		}

		protected override void OnPaint(PaintEventArgs e) 
		{
			Graphics graphics = e.Graphics;

			Pen pen;
			SolidBrush brush;
			SolidBrush textBrush;

			//Work out the colours that we should be using for the text and background
			if (m_state == States.Normal)
			{
				brush = new SolidBrush(m_NormalBtnColour);
				textBrush = new SolidBrush(m_NormalTxtColour);
				pen = new Pen(m_NormalTxtColour);
			}
			else
			{
				brush = new SolidBrush(m_PushedBtnColour);
				textBrush = new SolidBrush(m_PushedTxtColour);
				pen = new Pen(m_PushedTxtColour);
			}

			//Draw a rectangle and fill the inside
			graphics.FillRectangle(brush, 0, 0, Width, Height);
			graphics.DrawRectangle(pen, 0, 0, Width-1, Height-1);

			//Create a font based on the default font
			int fontHeight = 10;
			Font font = new Font(FontFamily.GenericSerif, fontHeight, FontStyle.Bold);

			//Find out the size of the text
			SizeF textSize = new SizeF();
			textSize = e.Graphics.MeasureString(Text, font);

			//Work out how to position the text centrally
			float x=0,y=0;
			if (textSize.Width < Width)
				x = (Width - textSize.Width) /2;
			if (textSize.Height < Height)
				y = (Height - textSize.Height) /2;

			//Draw the text in the centre of the button using the default font
			graphics.DrawString(Text, font, textBrush, x, y);
		}

#endregion
	}
}