原文:
C#屏幕截图
今天通过C#来实现一个简单的屏幕截图功能。实现思路，获取鼠标按下去的位置和鼠标左键释放的位置，计算这个区域的宽度和高度。然后通过 Graphics.CopyFromScreen 方法便可以获取到屏幕截图了。
下面通过C#+WPF来实现这个功能，代码如下：
XAML:
<Window x:Class="WPFCaptureScreenShot.CaptureWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="CaptureWindow"
AllowsTransparency="True"
WindowStyle="None"
Background="Black"
Opacity="0.1"
WindowState="Maximized"
MouseDown="CaptureWindow_MouseDown"
MouseMove="CaptureWindow_MouseMove">
<Canvas x:Name="CaptureCanvas">
</Canvas>
</Window>
public partial class CaptureWindow : Window { private double x; private double y; private double width; private double height; private bool isMouseDown = false; public CaptureWindow() { InitializeComponent(); } private void CaptureWindow_MouseDown(object sender, MouseButtonEventArgs e) { isMouseDown = true; x = e.GetPosition(null).X; y = e.GetPosition(null).Y; } private void CaptureWindow_MouseMove(object sender, System.Windows.Input.MouseEventArgs e) { if(isMouseDown) { // 1. 通过一个矩形来表示目前截图区域 System.Windows.Shapes.Rectangle rect = new System.Windows.Shapes.Rectangle(); double dx = e.GetPosition(null).X; double dy = e.GetPosition(null).Y; double rectWidth = Math.Abs(dx - x); double rectHeight = Math.Abs(dy - y); SolidColorBrush brush = new SolidColorBrush(Colors.White); rect.Width = rectWidth; rect.Height = rectHeight; rect.Fill = brush; rect.Stroke = brush; rect.StrokeThickness = 1; if (dx < x) { Canvas.SetLeft(rect, dx); Canvas.SetTop(rect, dy); } else { Canvas.SetLeft(rect, x); Canvas.SetTop(rect, y); } CaptureCanvas.Children.Clear(); CaptureCanvas.Children.Add(rect); if(e.LeftButton == MouseButtonState.Released) { CaptureCanvas.Children.Clear(); // 2. 获得当前截图区域 width = Math.Abs(e.GetPosition(null).X - x); height = Math.Abs(e.GetPosition(null).Y - y); if(e.GetPosition(null).X > x) { CaptureScreen(x, y, width, height); } else { CaptureScreen(e.GetPosition(null).X, e.GetPosition(null).Y, width, height); } isMouseDown = false; x = 0.0; y = 0.0; this.Close(); } } } private void CaptureScreen(double x, double y, double width, double height) { int ix = Convert.ToInt32(x); int iy = Convert.ToInt32(y); int iw = Convert.ToInt32(width); int ih = Convert.ToInt32(height); System.Drawing.Bitmap bitmap = new Bitmap(iw, ih); using(System.Drawing.Graphics graphics = Graphics.FromImage(bitmap)) { graphics.CopyFromScreen(ix, iy, 0, 0, new System.Drawing.Size(iw, ih)); SaveFileDialog dialog = new SaveFileDialog(); dialog.Filter = "Png Files|*.png"; if (dialog.ShowDialog() == System.Windows.Forms.DialogResult.OK) { bitmap.Save(dialog.FileName, ImageFormat.Png); } } }
运行效果：
源代码可以点击这里下载。
如果你有其他方式实现，欢迎与我分享。如果对代码有疑问，可以在评论中指出。感谢阅读。
