form1.cs

C#150例

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Drawing.Imaging; 

namespace Example054_使用颜色矩阵设置图像中的_Alpha_值
{
	/// <summary>
	/// Form1 的摘要说明。
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		/// <summary>
		/// 必需的设计器变量。
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			//
			// Windows 窗体设计器支持所必需的
			//
			InitializeComponent();

			//
			// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
			//
		}

		/// <summary>
		/// 清理所有正在使用的资源。
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{
			// 
			// Form1
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
			this.ClientSize = new System.Drawing.Size(292, 273);
			this.Name = "Form1";
			this.Text = "Form1";
			this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);

		}
		#endregion

		/// <summary>
		/// 应用程序的主入口点。
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new Form1());
		}

		private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
		{
			// Create the Bitmap object and load it with the texture image.
			Bitmap bitmap = new Bitmap("..\\..\\test.jpg");

			// Initialize the color matrix.
			// Note the value 0.8 in row 4, column 4.
			float[][] matrixItems ={ 
									   new float[] {1, 0, 0, 0, 0},
									   new float[] {0, 1, 0, 0, 0},
									   new float[] {0, 0, 1, 0, 0},
									   new float[] {0, 0, 0, 0.8f, 0}, 
									   new float[] {0, 0, 0, 0, 1}}; 
			ColorMatrix colorMatrix = new ColorMatrix(matrixItems);

			// Create an ImageAttributes object and set its color matrix.
			ImageAttributes imageAtt = new ImageAttributes();
			imageAtt.SetColorMatrix(
				colorMatrix,
				ColorMatrixFlag.Default,
				ColorAdjustType.Bitmap);

			// First draw a wide black line.
			e.Graphics.DrawLine(
				new Pen(Color.Black, 25),
				new Point(10, 35),
				new Point(200, 35));

			// Now draw the semitransparent bitmap image.
			int iWidth = bitmap.Width;
			int iHeight = bitmap.Height;
			e.Graphics.DrawImage(
				bitmap, 
				new Rectangle(30, 0, iWidth, iHeight),  // destination rectangle
				0.0f,                          // source rectangle x 
				0.0f,                          // source rectangle y
				iWidth,                        // source rectangle width
				iHeight,                       // source rectangle height
				GraphicsUnit.Pixel, 
				imageAtt);		
		}
	}
}