颜色拾取器（C#源码）

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Runtime.InteropServices; namespace GetColor
{ public partial class FrmGetColor : Form
    { public FrmGetColor()
        {
            InitializeComponent();
        } #region 定义快捷键 //如果函数执行成功，返回值不为0。 //如果函数执行失败，返回值为0。要得到扩展错误信息，调用GetLastError。  [DllImport("user32.dll", SetLastError = true)] public static extern bool RegisterHotKey(
        IntPtr hWnd, //要定义热键的窗口的句柄  int id, //定义热键ID（不能与其它ID重复）  KeyModifiers fsModifiers, //标识热键是否在按Alt、Ctrl、Shift、Windows等键时才会生效  Keys vk //定义热键的内容   );
        [DllImport("user32.dll", SetLastError = true)] public static extern bool UnregisterHotKey(
            IntPtr hWnd, //要取消热键的窗口的句柄  int id //要取消热键的ID   ); //定义了辅助键的名称（将数字转变为字符以便于记忆，也可去除此枚举而直接使用数值）   [Flags()] public enum KeyModifiers
        {
            None = 0,
            Alt = 1,
            Ctrl = 2,
            Shift = 4,
            WindowsKey = 8 } #endregion [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 FrmGetColor_Load(object sender, EventArgs e)
        { this.TopMost = true;
        } private void checkBox1_CheckedChanged(object sender, EventArgs e)
        { if (checkBox1.Checked == true)
            { this.TopMost = true;
            } else { this.TopMost = false;
            }
        } private void timer1_Tick(object sender, EventArgs e)
        {
            txtPoint.Text=Control.MousePosition.X.ToString() "," Control.MousePosition.Y.ToString();
            Point pt = new Point(Control.MousePosition.X, Control.MousePosition.Y);
            Color cl = GetColor(pt);
            panel1.BackColor = cl;
            txtRGB.Text = cl.R "," cl.G ","  cl.B;
            txtColor.Text = ColorTranslator.ToHtml(cl).ToString();
            RegisterHotKey(Handle, 81, KeyModifiers.Ctrl, Keys.F);
        } private void button1_Click(object sender, EventArgs e)
        {
            Application.Exit();
        } private void button2_Click(object sender, EventArgs e)
        {
            AboutBox1 ab = new AboutBox1();
            ab.ShowDialog();
        } private void label3_Click(object sender, EventArgs e)
        {
            System.Diagnostics.Process.Start("http://www.mrbccd.com");
        } protected override void WndProc(ref Message m)
        { const int WM_HOTKEY = 0x0312; //按快捷键  switch (m.Msg)
            { case WM_HOTKEY: switch (m.WParam.ToInt32())
                    { case 81: //按下的是CTRL F   Clipboard.SetText(txtColor.Text.Trim()); break;
                    } break;
            } base.WndProc(ref m);
        } private void FrmGetColor_Leave(object sender, EventArgs e)
        {

        } private void FrmGetColor_FormClosed(object sender, FormClosedEventArgs e)
        { //注销Id号为81的热键设定  UnregisterHotKey(Handle, 81);
        }
    }
}

s【实例截图】