目录

• 实践过程
• 效果
• 代码

实践过程

效果

代码

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

    #region 定义快捷键
    //如果函数执行成功，返回值不为。       
    //如果函数执行失败，返回值为。要得到扩展错误信息，调用GetLastError。        
    [DllImport("user.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("user.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 =,
        Alt =,
        Ctrl =,
        Shift =,
        WindowsKey =
    }
    #endregion

    #region 获取鼠标像素的RGB
    [DllImport("gdi.dll")]
    static public extern uint GetPixel(IntPtr hDC, int XPos, int YPos);
    [DllImport("gdi.dll")]
    static public extern IntPtr CreateDC(string driverName, string deviceName, string output, IntPtr lpinitData);
    [DllImport("gdi.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)) >>));
    }
    static public byte GetBValue(uint color)
    {
        return ((byte)((color) >>));
    }
    static public byte GetAValue(uint color)
    {
        return ((byte)((color) >>));
    }
    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);
    }
    #endregion

    
    int screenWidth;        //屏幕宽度
    int screenHeight;       //屏幕高度
    int mx;                 //鼠标x坐标
    int my;                 //鼠标y坐标
    const int imgWidth =;//放大后图片的宽度
    const int imgHeight =;//放大后图片的高度

    private void Form_Load(object sender, EventArgs e)
    {
        this.Location = new Point(,0);
        screenWidth = Screen.PrimaryScreen.WorkingArea.Width;
        screenHeight = Screen.PrimaryScreen.WorkingArea.Height;
        this.TopMost = true;
    }

    private void timer_Tick(object sender, EventArgs e)
    {
        RegisterHotKey(Handle,, KeyModifiers.None, Keys.Escape);
        mx = Control.MousePosition.X;
        my = Control.MousePosition.Y;
        lblmPos.Text="("+mx.ToString()+","+my.ToString()+")";
        Point pt = new Point(mx,my);
        Color cl = GetColor(pt);
        lblRGB.Text = "(" + cl.R.ToString() + "," + cl.G.ToString() + "," + cl.B + ")";
        if (mx <= this.Width&&my<=this.Height)
        {
            this.Location = new Point(screenWidth-this.Width,);
        }
        if (mx >= screenWidth - this.Width&&my<=this.Height)
        {
            this.Location = new Point(,0);
        }
        Bitmap bt = new Bitmap(imgWidth/,imgHeight/2);
        Graphics g = Graphics.FromImage(bt);
        g.CopyFromScreen(new Point(Cursor.Position.X-imgWidth/,Cursor.Position.Y-imgHeight/4),new Point(0,0),new Size(imgWidth/2,imgHeight/2));
        IntPtr dc = g.GetHdc();
        g.ReleaseHdc(dc);
        pictureBox.Image = (Image)bt;
       
    }

    protected override void WndProc(ref Message m)
    {
        const int WM_HOTKEY =x0312;
        //按快捷键     
        switch (m.Msg)
        {
            case WM_HOTKEY:
                switch (m.WParam.ToInt())
                {
                    case:    //按下的是ESC     
                        Application.Exit();
                        break;
                }
                break;
        }
        base.WndProc(ref m);
    }

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

    private void pictureBox_Paint(object sender, PaintEventArgs e)
    {
        Graphics g = e.Graphics;
        g.DrawLine(new Pen(Color.Red), new PointF(pictureBox.Width / 2, 0), new PointF(pictureBox1.Width / 2,pictureBox1.Height));
        g.DrawLine(new Pen(Color.Red,), new PointF(0, pictureBox1.Height / 2), new PointF(pictureBox1.Width, pictureBox1.Height/2));
    }
}
partial class Form
{
    /// <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.timer = new System.Windows.Forms.Timer(this.components);
        this.label = new System.Windows.Forms.Label();
        this.lblmPos = new System.Windows.Forms.Label();
        this.label = new System.Windows.Forms.Label();
        this.label = new System.Windows.Forms.Label();
        this.lblRGB = new System.Windows.Forms.Label();
        this.pictureBox = new System.Windows.Forms.PictureBox();
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox)).BeginInit();
        this.SuspendLayout();
        // 
        // timer
        // 
        this.timer.Enabled = true;
        this.timer.Tick += new System.EventHandler(this.timer1_Tick);
        // 
        // label
        // 
        this.label.AutoSize = true;
        this.label.BackColor = System.Drawing.Color.Transparent;
        this.label.ForeColor = System.Drawing.Color.Black;
        this.label.Location = new System.Drawing.Point(12, 122);
        this.label.Name = "label2";
        this.label.Size = new System.Drawing.Size(65, 12);
        this.label.TabIndex = 2;
        this.label.Text = "鼠标位置：";
        // 
        // lblmPos
        // 
        this.lblmPos.AutoSize = true;
        this.lblmPos.BackColor = System.Drawing.Color.Transparent;
        this.lblmPos.ForeColor = System.Drawing.Color.Black;
        this.lblmPos.Location = new System.Drawing.Point(, 122);
        this.lblmPos.Name = "lblmPos";
        this.lblmPos.Size = new System.Drawing.Size(, 12);
        this.lblmPos.TabIndex =;
        this.lblmPos.Text = "label";
        // 
        // label
        // 
        this.label.AutoSize = true;
        this.label.BackColor = System.Drawing.Color.Transparent;
        this.label.ForeColor = System.Drawing.Color.Black;
        this.label.Location = new System.Drawing.Point(10, 47);
        this.label.Name = "label3";
        this.label.Size = new System.Drawing.Size(125, 12);
        this.label.TabIndex = 5;
        this.label.Text = "⊙ 当前像素的RGB值：";
        // 
        // label
        // 
        this.label.AutoSize = true;
        this.label.BackColor = System.Drawing.Color.Transparent;
        this.label.ForeColor = System.Drawing.Color.Black;
        this.label.Location = new System.Drawing.Point(10, 73);
        this.label.Name = "label4";
        this.label.Size = new System.Drawing.Size(125, 12);
        this.label.TabIndex = 6;
        this.label.Text = "⊙ 按ESC键关闭放大镜";
        // 
        // lblRGB
        // 
        this.lblRGB.AutoSize = true;
        this.lblRGB.BackColor = System.Drawing.Color.Transparent;
        this.lblRGB.ForeColor = System.Drawing.Color.Black;
        this.lblRGB.Location = new System.Drawing.Point(, 47);
        this.lblRGB.Name = "lblRGB";
        this.lblRGB.Size = new System.Drawing.Size(, 12);
        this.lblRGB.TabIndex =;
        this.lblRGB.Text = "label";
        // 
        // pictureBox
        // 
        this.pictureBox.BackColor = System.Drawing.Color.White;
        this.pictureBox.Location = new System.Drawing.Point(3, 146);
        this.pictureBox.Name = "pictureBox1";
        this.pictureBox.Size = new System.Drawing.Size(234, 134);
        this.pictureBox.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
        this.pictureBox.TabIndex = 8;
        this.pictureBox.TabStop = false;
        this.pictureBox.Paint += new System.Windows.Forms.PaintEventHandler(this.pictureBox1_Paint);
        // 
        // Form
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(F, 12F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.BackgroundImage = global::ScreenBlowupGlass.Properties.Resources.bg;
        this.ClientSize = new System.Drawing.Size(, 284);
        this.Controls.Add(this.pictureBox);
        this.Controls.Add(this.lblRGB);
        this.Controls.Add(this.label);
        this.Controls.Add(this.label);
        this.Controls.Add(this.lblmPos);
        this.Controls.Add(this.label);
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
        this.MaximizeBox = false;
        this.MinimizeBox = false;
        this.Name = "Form";
        this.Text = "屏幕放大镜";
        this.Load += new System.EventHandler(this.Form_Load);
        this.FormClosed += new System.Windows.Forms.FormClosedEventHandler(this.Form_FormClosed);
        ((System.ComponentModel.ISupportInitialize)(this.pictureBox)).EndInit();
        this.ResumeLayout(false);
        this.PerformLayout();

    }

    #endregion

    private System.Windows.Forms.Timer timer;
    private System.Windows.Forms.Label label;
    private System.Windows.Forms.Label lblmPos;
    private System.Windows.Forms.Label label;
    private System.Windows.Forms.Label label;
    private System.Windows.Forms.Label lblRGB;
    private System.Windows.Forms.PictureBox pictureBox;
}