基于C#实现屏幕取色器的示例详解

实践过程

效果

代码

public partial class Form1 : Form
{
   public Form1()
   {
       InitializeComponent();
   }

[DllImport("gdi32.dll")]
   static public extern uint GetPixel(IntPtr hDC, int XPos, int YPos);

[DllImport("gdi32.dll")]
   static public extern IntPtr CreateDC(string driverName, string deviceName, string output, IntPtr lpinitData);

[DllImport("gdi32.dll")]
   static public extern bool DeleteDC(IntPtr DC);

static public byte GetRValue(uint color)
   {
       return (byte) color;
   }

static public byte GetGValue(uint color)
   {
       return ((byte) (((short) (color)) >> 8));
   }

static public byte GetBValue(uint color)
   {
       return ((byte) ((color) >> 16));
   }

static public byte GetAValue(uint color)
   {
       return ((byte) ((color) >> 24));
   }

public Color GetColor(Point screenPoint)
   {
       IntPtr displayDC = CreateDC("DISPLAY", null, null, IntPtr.Zero);
       uint colorref = GetPixel(displayDC, screenPoint.X, screenPoint.Y);
       DeleteDC(displayDC);
       byte Red = GetRValue(colorref);
       byte Green = GetGValue(colorref);
       byte Blue = GetBValue(colorref);
       return Color.FromArgb(Red, Green, Blue);
   }

private void Form1_Load(object sender, EventArgs e)
   {
   }

private void timer1_Tick(object sender, EventArgs e)
   {
       Point pt = new Point(Control.MousePosition.X, Control.MousePosition.Y);
       Color cl = GetColor(pt);
       panel1.BackColor = cl;
   }
}

partial class Form1
{
   /// <summary>
   /// 必需的设计器变量。
   /// </summary>
   private System.ComponentModel.IContainer components = null;

/// <summary>
   /// 清理所有正在使用的资源。
   /// </summary>
   /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
   protected override void Dispose(bool disposing)
   {
       if (disposing && (components != null))
       {
           components.Dispose();
       }
       base.Dispose(disposing);
   }

#region Windows 窗体设计器生成的代码

/// <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()
   {
       this.components = new System.ComponentModel.Container();
       this.timer1 = new System.Windows.Forms.Timer(this.components);
       this.panel1 = new System.Windows.Forms.Panel();
       this.SuspendLayout();
       //
       // timer1
       //
       this.timer1.Enabled = true;
       this.timer1.Tick += new System.EventHandler(this.timer1_Tick);
       //
       // panel1
       //
       this.panel1.Location = new System.Drawing.Point(12, 12);
       this.panel1.Name = "panel1";
       this.panel1.Size = new System.Drawing.Size(200, 100);
       this.panel1.TabIndex = 0;
       //
       // Form1
       //
       this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
       this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
       this.ClientSize = new System.Drawing.Size(535, 298);
       this.Controls.Add(this.panel1);
       this.Name = "Form1";
       this.Text = "Form1";
       this.Load += new System.EventHandler(this.Form1_Load);
       this.ResumeLayout(false);

}

#endregion

private System.Windows.Forms.Timer timer1;
   private System.Windows.Forms.Panel panel1;
}

来源：https://zhima.blog.csdn.net/article/details/128123604