截图小工具开发笔记
一、开发环境及工具
Windows 7 系统，开发软件为Microsoft Visual Studio Ultimate 2012
二、实现的功能
屏幕截屏，保存到图片或者保存到剪切板。截屏范围可以随意移动或者改变大小，自由度很高。先预览一下效果：
三、实现原理
共2个窗体，1个是主窗体，主要功能进行热键设置，抓取屏幕到图片传给另一个窗体，另一个窗体对传过来的图片继续截取等操作。
四、开发手记
1.新建winform项目
2.主界面设计如图:
窗体主要属性设置如下：
//窗口样式 this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog; //窗口图标 this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon"))); //禁止最大化 this.MaximizeBox = false; //窗口名称 this.Name = "PicCut"; //窗口初始位置为屏幕中心 this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen; //窗口标题为“截图设置” this.Text = "截图设置"; //窗口浮在所有窗口上面 this.TopMost = true;
此窗口内主要包括2个label控件，1个ComboBox和1个PictureBox，摆放位置如上图。label用于显示文字说明；ComboBox用于显示热键0—9个数字供选择；PictureBox用于显示二维码图片。
3.主界面的主要功能是对热键进行设置，同时我们程序运行，该界面自动最小化到托盘，双击进行截图，有机显示上述主界面进行设置，设置完毕可以最小化自动到托盘，点击关闭程序会自动退出。
（1）自动到托盘
主界面拖入“notifyIcon”，主要属性设置如下图，其中Text是鼠标滑动到拖盘区域图标上的提示；Icon是托盘图标；Visible设置为false，默认不显示托盘区域图标。
主要程序代码。窗体载入时，最小化窗体，同时设置ComboBox空间的默认值。
private void PicCut_Load(object sender, EventArgs e) {
this.WindowState = FormWindowState.Minimized; NumberCbox.SelectedIndex = CutPicSet.Default.KeyNumber; }
窗口大小发生变化时，如果窗口最小化，隐藏当前窗体，托盘区域显示图标。
private void PicCut_SizeChanged(object sender, EventArgs e) { if (this.WindowState == FormWindowState.Minimized) { this.Hide(); MinNot.Visible = true; } }
上述两段代码实现了，程序开始运行时候，窗口最小化隐藏，同时托盘区域显示图标。
（2）托盘图标左键双击进行截图操作
private void MinNot_MouseDoubleClick(object sender, MouseEventArgs e) { if (e.Button==MouseButtons.Left) {
//显示截图窗体
ShowCutPic(); } }
ShowCutPic函数：
protected void ShowCutPic() { // 创建的空白图片和屏幕大小一样大的图片 Bitmap CatchBmp = new Bitmap(Screen.AllScreens[0].Bounds.Width, Screen.AllScreens[0].Bounds.Height); // 我们可以通过Graphics这个类在这个空白图片上画图 Graphics g = Graphics.FromImage(CatchBmp); // 把屏幕图片拷贝到我们创建的空白图片 CatchBmp中 g.CopyFromScreen(new Point(0, 0), new Point(0, 0), new Size(Screen.AllScreens[0].Bounds.Width, Screen.AllScreens[0].Bounds.Height)); //这个我们截图的窗体创建截图窗体 cutter = new CutPic(); // 截图窗体的图片属性设置我们刚才新建的图片; cutter.Image = CatchBmp; //显示窗体 cutter.ShowDialog(); }
（3）托盘图标右键单击显示界面设置
private void MinNot_MouseClick(object sender, MouseEventArgs e) { if (e.Button== MouseButtons.Right) { //显示主窗体 this.Show(); //隐藏托盘图标 MinNot.Visible = false; //当前窗口普通设置 this.WindowState = FormWindowState.Normal; } }
（4）热键设置
/// <summary> /// 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。 /// </summary> /// <param name="hWnd">要定义热键的窗口的句柄</param> /// <param name="id">定义热键ID（不能与其它ID重复）</param> /// <param name="fsModifiers">标识热键是否在按Alt、Ctrl、Shift、Windows等键时才会生效</param> /// <param name="vk">定义热键的内容</param> /// <returns></returns> [DllImport("user32.dll", SetLastError = true)] public static extern bool RegisterHotKey(IntPtr hWnd, int id, KeyModifiers fsModifiers, Keys vk); /// <summary> /// 注销热键 /// </summary> /// <param name="hWnd">要取消热键的窗口的句柄</param> /// <param name="id">要取消热键的ID</param> /// <returns></returns> [DllImport("user32.dll", SetLastError = true)] public static extern bool UnregisterHotKey(IntPtr hWnd, int id); /// <summary> /// 辅助键名称。 /// Alt, Ctrl, Shift, WindowsKey /// </summary> [Flags()] public enum KeyModifiers { None = 0, Alt = 1, Ctrl = 2, Shift = 4, WindowsKey = 8 } /// <summary> /// 注册热键 /// </summary> /// <param name="hwnd">窗口句柄</param> /// <param name="hotKey_id">热键ID</param> /// <param name="keyModifiers">组合键</param> /// <param name="key">热键</param> public static void RegHotKey(IntPtr hwnd, int hotKeyId, KeyModifiers keyModifiers, Keys key) { if (!RegisterHotKey(hwnd, hotKeyId, keyModifiers, key)) { int errorCode = Marshal.GetLastWin32Error(); if (errorCode == 1409) { MessageBox.Show("热键被占用 ！"); } else { MessageBox.Show("注册热键失败！错误代码：" + errorCode); } } } /// <summary> /// 注销热键 /// </summary> /// <param name="hwnd">窗口句柄</param> /// <param name="hotKey_id">热键ID</param> public static void UnRegHotKey(IntPtr hwnd, int hotKeyId) { //注销指定的热键 UnregisterHotKey(hwnd, hotKeyId); }
private const int WM_HOTKEY = 0x312; //窗口消息-热键 private const int WM_CREATE = 0x1; //窗口消息-创建 private const int WM_DESTROY = 0x2; //窗口消息-销毁 private const int Space = 0x3572; //热键ID protected override void WndProc(ref Message m) { base.WndProc(ref m); switch (m.Msg) { case WM_HOTKEY: //窗口消息-热键ID switch (m.WParam.ToInt32()) { case Space: //热键ID //按下热键显示截图窗体 ShowCutPic(); break; default: break; } break; case WM_CREATE: //窗口消息-创建 SetHotKey(CutPicSet.Default.KeyNumber); break; case WM_DESTROY: //窗口消息-销毁 UnRegHotKey(Handle, Space); //销毁热键 break; default: break; } } public void SetHotKey(int keynumber) { if (keynumber == 0) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D0); } else if (keynumber == 1) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D1); } else if (keynumber == 2) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D2); } else if (keynumber == 3) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D3); } else if (keynumber == 4) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D4); } else if (keynumber == 5) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D5); } else if (keynumber == 6) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D6); } else if (keynumber == 7) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D7); } else if (keynumber == 8) { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D8); } else { RegHotKey(Handle, Space, KeyModifiers.Ctrl, Keys.D9); } }
（5）图形热键设置
private void NumberCbox_SelectedIndexChanged(object sender, EventArgs e) { //把配置文件设置NumberCbox的选择值 CutPicSet.Default.KeyNumber = NumberCbox.SelectedIndex; CutPicSet.Default.Save(); //先卸载原来注册的热键 UnRegHotKey(Handle, Space); //从新设置选择的热键 SetHotKey(NumberCbox.SelectedIndex); }
4、截图界面设计
新建窗体CutPic，名称与之前的名称相对应，主要属性设置如下：
Name：CutPic
WindowState:Maximized
TopMost:true
FormBorderStyle:None
5、截图功能实现
主要代码如下：
private Point m_ptStart; //起始点位置 private Point m_ptCurrent; //当前鼠标位置 private Point m_ptTempForMove; //移动选框的时候临时用 private Rectangle m_rectClip; //限定鼠标活动的区域 private Rectangle[] m_rectDots = new Rectangle[8]; //八个控制点 protected bool m_bMoving; protected bool m_bChangeWidth; protected bool m_bChangeHeight; protected bool m_bMouseHover; private bool _IsDrawed; /// 获取当前是否已经选择区域 private Image _Image; /// /// 要裁剪的图像 /// [Description("要裁剪的图像"), Category("Customs")] public Image Image { get { return _Image; } set { if (value == this._Image) return; _Image = value; // this.Clear(); } } private Color _MaskColor = Color.FromArgb(125, 0, 0, 0); /// /// 遮罩颜色 /// [Description("遮罩颜色"), Category("Customs")] public Color MaskColor { get { return _MaskColor; } set { if (_MaskColor == value) return; _MaskColor = value; if (this._Image != null) this.Invalidate(); } } private Rectangle _SelectedRectangle;/// 获取或设置悬着区域 public CutPic() { SetStyle(ControlStyles.UserPaint, true); SetStyle(ControlStyles.AllPaintingInWmPaint, true); // 禁止擦除背景. SetStyle(ControlStyles.DoubleBuffer, true); // 双缓冲 InitializeComponent(); } private void CutPic_MouseDown(object sender, MouseEventArgs e) { if (this._Image == null) { return;//Image属性null或者已经锁定选择 直接返回 } m_ptStart = e.Location; m_bChangeHeight = true; m_bChangeWidth = true; //判断若不在限定范围内操作 返回 m_rectClip = this.DisplayRectangle; Size sz = this.Size; sz = this.Size; m_rectClip.Intersect(new Rectangle(Point.Empty, sz)); m_rectClip.Width++; m_rectClip.Height++; Cursor.Clip = RectangleToScreen(m_rectClip); if (ToolsPanel.Visible==true) { ToolsPanel.Visible = false; } //如果 已经选择区域 若鼠标点下 判断是否在控制顶点上 if (this._IsDrawed) { this._IsDrawed = false; //默认表示 要更改选取设置 清楚IsDrawed属性 if (m_rectDots[0].Contains(e.Location)) { m_ptStart.X = this._SelectedRectangle.Right; m_ptStart.Y = this._SelectedRectangle.Bottom; } else if (m_rectDots[1].Contains(e.Location)) { m_ptStart.Y = this._SelectedRectangle.Bottom; m_bChangeWidth = false; } else if (m_rectDots[2].Contains(e.Location)) { m_ptStart.X = this._SelectedRectangle.X; m_ptStart.Y = this._SelectedRectangle.Bottom; } else if (m_rectDots[3].Contains(e.Location)) { m_ptStart.X = this._SelectedRectangle.Right; m_bChangeHeight = false; } else if (m_rectDots[4].Contains(e.Location)) { m_ptStart.X = this._SelectedRectangle.X; m_bChangeHeight = false; } else if (m_rectDots[5].Contains(e.Location)) { m_ptStart.X = this._SelectedRectangle.Right; m_ptStart.Y = this._SelectedRectangle.Y; } else if (m_rectDots[6].Contains(e.Location)) { m_ptStart.Y = this._SelectedRectangle.Y; m_bChangeWidth = false; } else if (m_rectDots[7].Contains(e.Location)) { m_ptStart = this._SelectedRectangle.Location; } else if (this._SelectedRectangle.Contains(e.Location)) { m_bMoving = true; m_bChangeWidth = false; m_bChangeHeight = false; } else { this._IsDrawed = true; } //若以上条件不成立 表示不需要更改设置 } } private void CutPic_MouseClick(object sender, MouseEventArgs e) { if (MouseButtons.Right==e.Button) { this.DialogResult = DialogResult.OK; this.Close(); } } private void CutPic_Paint(object sender, PaintEventArgs e) { Graphics g = e.Graphics; if (_Image!=null) { g.DrawImage(this._Image,0,0,this._Image.Width,this._Image.Height);//原图 using (SolidBrush sb = new SolidBrush(this._MaskColor)) { g.FillRectangle(sb, this.ClientRectangle);//遮罩 } if (!this._SelectedRectangle.IsEmpty) this.DrawSelectedRectangle(g);//选框 } SetPanleLocation(); } private void CutPic_Load(object sender, EventArgs e) { for (int i = 0; i < 8; i++) { m_rectDots[i].Size = new Size(5, 5); } m_ptTempForMove = this.DisplayRectangle.Location; } private void CutPic_MouseMove(object sender, MouseEventArgs e) { m_ptCurrent = e.Location; if (this._Image == null) { return; } if (this._IsDrawed) {//如果已经绘制 移动过程中判断是否需要设置鼠标样式 this.SetCursorStyle(e.Location); } else if (e.Button == MouseButtons.Left) {//否则可能表示在选择区域或重置大小 if (m_bChangeWidth) {//是否允许选区宽度改变 如重置大小时候 拉动上边和下边中点时候 this._SelectedRectangle.X = e.Location.X > m_ptStart.X ? m_ptStart.X : e.Location.X; this._SelectedRectangle.Width = Math.Abs(e.Location.X - m_ptStart.X); } if (m_bChangeHeight) { this._SelectedRectangle.Y = e.Location.Y > m_ptStart.Y ? m_ptStart.Y : e.Location.Y; this._SelectedRectangle.Height = Math.Abs(e.Location.Y - m_ptStart.Y); } if (m_bMoving) {//如果是移动选区 判断选区移动范围 int tempX = m_ptTempForMove.X + e.X - m_ptStart.X; int tempY = m_ptTempForMove.Y + e.Y - m_ptStart.Y; if (tempX < 0) tempX = 0; if (tempY < 0) tempY = 0; if (this._SelectedRectangle.Width + tempX >= m_rectClip.Width) tempX = m_rectClip.Width - this._SelectedRectangle.Width - 1; if (this._SelectedRectangle.Height + tempY >= m_rectClip.Height) tempY = m_rectClip.Height - this._SelectedRectangle.Height - 1; this._SelectedRectangle.X = tempX; this._SelectedRectangle.Y = tempY; } this.Invalidate(); } else if (!this._IsDrawed) { this.Invalidate();//否则 在需要绘制放大镜并且还没有选好区域同时 都重绘 } } /// /// 判断鼠标当前位置显示样式 /// /// 鼠标坐标 protected virtual void SetCursorStyle(Point pt) { if (m_rectDots[0].Contains(pt) || m_rectDots[7].Contains(pt)) this.Cursor = Cursors.SizeNWSE; else if (m_rectDots[1].Contains(pt) || m_rectDots[6].Contains(pt)) this.Cursor = Cursors.SizeNS; else if (m_rectDots[2].Contains(pt) || m_rectDots[5].Contains(pt)) this.Cursor = Cursors.SizeNESW; else if (m_rectDots[3].Contains(pt) || m_rectDots[4].Contains(pt)) this.Cursor = Cursors.SizeWE; else if (this._SelectedRectangle.Contains(pt)) this.Cursor = Cursors.SizeAll; else this.Cursor = Cursors.Default; } private void CutPic_MouseUp(object sender, MouseEventArgs e) { this._IsDrawed = !this._SelectedRectangle.IsEmpty; m_ptTempForMove = this._SelectedRectangle.Location; m_bMoving = false; m_bChangeWidth = false; m_bChangeHeight = false; Cursor.Clip = Rectangle.Empty; ToolsPanel.Visible = true; this.Invalidate(); } public void SetPanleLocation() { ToolsPanel.Left = this._SelectedRectangle.Left + this._SelectedRectangle.Width - ToolsPanel.Width; ToolsPanel.Top = this._SelectedRectangle.Top+this._SelectedRectangle.Height+5; } /// /// 绘制选框 /// /// 绘图表面 protected virtual void DrawSelectedRectangle(Graphics g) { m_rectDots[0].Y = m_rectDots[1].Y = m_rectDots[2].Y = this._SelectedRectangle.Y - 2; m_rectDots[5].Y = m_rectDots[6].Y = m_rectDots[7].Y = this._SelectedRectangle.Bottom - 2; m_rectDots[0].X = m_rectDots[3].X = m_rectDots[5].X = this._SelectedRectangle.X - 2; m_rectDots[2].X = m_rectDots[4].X = m_rectDots[7].X = this._SelectedRectangle.Right - 2; m_rectDots[3].Y = m_rectDots[4].Y = this._SelectedRectangle.Y + this._SelectedRectangle.Height / 2 - 2; m_rectDots[1].X = m_rectDots[6].X = this._SelectedRectangle.X + this._SelectedRectangle.Width / 2 - 2; g.DrawImage(this._Image, this._SelectedRectangle, this._SelectedRectangle, GraphicsUnit.Pixel); g.DrawRectangle(Pens.Cyan, this._SelectedRectangle.Left, this._SelectedRectangle.Top, this._SelectedRectangle.Width - 1, this._SelectedRectangle.Height - 1); foreach (Rectangle rect in m_rectDots) g.FillRectangle(Brushes.Yellow, rect); string str = string.Format("X:{0} Y:{1} W:{2} H:{3}", this._SelectedRectangle.Left, this._SelectedRectangle.Top, this._SelectedRectangle.Width, this._SelectedRectangle.Height); Size szStr = g.MeasureString(str, this.Font).ToSize(); Point ptStr = new Point(this._SelectedRectangle.Left, this._SelectedRectangle.Top - szStr.Height - 5); if (ptStr.Y < 0) ptStr.Y = this._SelectedRectangle.Top + 5; if (ptStr.X + szStr.Width > this.Width) ptStr.X = this.Width - szStr.Width; using (SolidBrush sb = new SolidBrush(Color.FromArgb(125, 0, 0, 0))) { g.FillRectangle(sb, new Rectangle(ptStr, szStr)); g.DrawString(str, this.Font, Brushes.White, ptStr); } } private void SaveBT_Click(object sender, EventArgs e) { SaveFileDialog saveFileDialog = new SaveFileDialog(); saveFileDialog.FileName = DateTime.Now.ToString("yyyyMMddhhmmss"); saveFileDialog.Filter = "png|*.png|bmp|*.bmp|jpg|*.jpg|gif|*.gif"; if (saveFileDialog.ShowDialog() != DialogResult.Cancel) { System.Drawing.Rectangle cropArea = new System.Drawing.Rectangle(_SelectedRectangle.X, _SelectedRectangle.Y, _SelectedRectangle.Width, _SelectedRectangle.Height); Bitmap bmpImage = new Bitmap(this._Image); Bitmap bmpCrop = bmpImage.Clone(cropArea, bmpImage.PixelFormat); bmpCrop.Save(saveFileDialog.FileName); this.DialogResult = DialogResult.OK; this.Close(); } else { this.Focus(); } } private void CutPic_MouseDoubleClick(object sender, MouseEventArgs e) { if (this._SelectedRectangle.Contains(e.Location)) { //复制图片到剪切板 System.Drawing.Rectangle cropArea = new System.Drawing.Rectangle(_SelectedRectangle.X, _SelectedRectangle.Y, _SelectedRectangle.Width, _SelectedRectangle.Height); Bitmap bmpImage = new Bitmap(this._Image); Bitmap bmpCrop = bmpImage.Clone(cropArea, bmpImage.PixelFormat); Clipboard.SetImage(bmpCrop); this.DialogResult = DialogResult.OK; this.Close(); } } //如果按下ESC键退出截图功能 private void CutPic_KeyUp(object sender, KeyEventArgs e) { if (e.KeyValue==27) { this.DialogResult = DialogResult.OK; this.Close(); } }
这样截图功能就已经实现了。源代码下载，请点击
