C# WPF 截屏功能
原理： 在屏幕的分别使用左、上、下和右四个矩形填满屏幕，在鼠标按下拖动的时候，获取鼠标拖动形成的矩形区域。松开鼠标后，将矩形区域内的屏幕保存为图片
ScreenCutWnd.xaml
<Window x:Class="Goldou_Comment_WPF.Comment.ScreenCutWnd"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Goldou_Comment_WPF.Comment"
mc:Ignorable="d"
Title="ScreenCutWnd" Height="450" Width="800" WindowStyle="None" AllowsTransparency="True" Background="Transparent" >
<Canvas x:Name="DrawingBoard" MouseLeftButtonDown="DrawingBoard_MouseLeftButtonDown" MouseLeftButtonUp="DrawingBoard_MouseLeftButtonUp" MouseMove="DrawingBoard_MouseMove" >
<Rectangle x:Name="rectangleLeft" Fill="Black" Opacity="0.3"></Rectangle>
<Rectangle x:Name="rectangleTop" Fill="Black" Opacity="0.3"></Rectangle>
<Rectangle x:Name="rectangleRight" Fill="Black" Opacity="0.3"></Rectangle>
<Rectangle x:Name="rectangleBottom" Fill="Black" Opacity="0.3"></Rectangle>
<Border x:Name="ScreenBorder" BorderBrush="LightGreen" Visibility="Hidden" BorderThickness="0.25" ></Border>
<WrapPanel x:Name="WrapPanelBtn" Visibility="Hidden">
<Button x:Name="SaveBtn" Style="{StaticResource ButtonSuccess}" Margin="0,0,10,0" Content="保存" Click="Btn_Click"></Button>
<Button x:Name="CancelBtn" Style="{StaticResource ButtonDanger}" Content="取消" Click="Btn_Click"></Button>
</WrapPanel>
</Canvas>
</Window>
ScreenCutWnd.xaml.cs
using System;
using System.Collections.Generic;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
namespace Goldou_Comment_WPF.Comment
{
/// <summary>
/// ScreenCutWnd.xaml 的交互逻辑
/// </summary>
public partial class ScreenCutWnd : Window
{
private Rect rect;
private Point pointStart, pointEnd;
private bool isMouseUp = false;
private bool IsFullScreen = false; //是否是截的全屏
public ScreenCutWnd()
{
InitializeComponent();
try
{
this.Left = 0;
this.Top = 0;
this.Width = SystemParameters.PrimaryScreenWidth;
this.Height = SystemParameters.PrimaryScreenHeight;
this.DrawingBoard.Width = SystemParameters.PrimaryScreenWidth;
this.DrawingBoard.Height = SystemParameters.PrimaryScreenHeight;
this.DrawingBoard.Background = new ImageBrush(tools.ChangeBitmapToImageSource(CaptureScreen()));
rectangleLeft.Height = this.Height;
rectangleLeft.Width = this.Width;
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
}
private void DrawingBoard_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
try
{
if (!isMouseUp)
{
if (ScreenBorder.Visibility == Visibility.Visible)
{
ScreenBorder.Visibility = Visibility.Hidden;
}
pointStart = e.GetPosition(DrawingBoard);
pointEnd = pointStart;
rect = new Rect(pointStart, pointEnd);
}
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
e.Handled = true;
}
private void DrawingBoard_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
try
{
if (rect.Width + 2 >= this.Width&& rect.Height + 2 >= this.Height)
{
IsFullScreen = true;
}
else
{
IsFullScreen = false;
}
if (!isMouseUp && rect.Width > 0 && rect.Height > 0)
{
WrapPanelBtn.Visibility = Visibility.Visible;
if (rect.Width+2>= this.Width)
{
Canvas.SetLeft(this.WrapPanelBtn, rect.Width - this.WrapPanelBtn.ActualWidth);
}
if (rect.Height+2>= this.Height)
{
Canvas.SetTop(this.WrapPanelBtn, rect.Height - this.WrapPanelBtn.ActualHeight);
}
else
{
Canvas.SetLeft(this.WrapPanelBtn, rect.X + rect.Width - this.WrapPanelBtn.ActualWidth);
Canvas.SetTop(this.WrapPanelBtn, rect.Y + rect.Height + 4);
}
isMouseUp = true;
}
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
e.Handled = true;
}
private void DrawingBoard_MouseMove(object sender, MouseEventArgs e)
{
try
{
if (e.LeftButton == MouseButtonState.Pressed && !isMouseUp)
{
if (ScreenBorder.Visibility != Visibility.Visible)
{
ScreenBorder.Visibility = Visibility.Visible;
}
Point current = e.GetPosition(DrawingBoard);
MoveAllRectangle(current);
}
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
e.Handled = true;
}
protected override void OnKeyDown(KeyEventArgs e)
{
try
{
if (e.Key == Key.Escape)
{
this.Close();
}
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
}
private void MoveAllRectangle(Point current)
{
try
{
pointEnd = current;
rect = new Rect(pointStart, pointEnd);
this.rectangleLeft.Width = rect.X;
this.rectangleLeft.Height = DrawingBoard.Height;
Canvas.SetLeft(this.rectangleTop, this.rectangleLeft.Width);
this.rectangleTop.Width = rect.Width;
double h = 0.0;
if (current.Y < pointStart.Y)
h = current.Y;
else
h = current.Y - rect.Height;
this.rectangleTop.Height = h;
Canvas.SetLeft(this.rectangleRight, this.rectangleLeft.Width + rect.Width);
this.rectangleRight.Width = DrawingBoard.Width - (rect.Width + this.rectangleLeft.Width);
this.rectangleRight.Height = DrawingBoard.Height;
Canvas.SetLeft(this.rectangleBottom, this.rectangleLeft.Width);
Canvas.SetTop(this.rectangleBottom, rect.Height + this.rectangleTop.Height);
this.rectangleBottom.Width = rect.Width;
this.rectangleBottom.Height = DrawingBoard.Height - (rect.Height + this.rectangleTop.Height);
this.ScreenBorder.Height = rect.Height;
this.ScreenBorder.Width = rect.Width;
Canvas.SetLeft(this.ScreenBorder, rect.X);
Canvas.SetTop(this.ScreenBorder, rect.Y);
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
}
/// <summary>
/// 捕获屏幕
/// </summary>
/// <returns></returns>
private System.Drawing.Bitmap CaptureScreen()
{
var bmpCaptured = new System.Drawing.Bitmap((int)SystemParameters.PrimaryScreenWidth, (int)SystemParameters.PrimaryScreenHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bmpCaptured))
{
g.SmoothingMode = SmoothingMode.AntiAlias;
g.CompositingQuality = CompositingQuality.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;
g.PixelOffsetMode = PixelOffsetMode.HighQuality;
g.CopyFromScreen(0, 0, 0, 0, bmpCaptured.Size, System.Drawing.CopyPixelOperation.SourceCopy);
}
return bmpCaptured;
}
private void Btn_Click(object sender, RoutedEventArgs e)
{
try
{
Button button = sender as Button;
switch (button.Name)
{
case "SaveBtn":
if (IsFullScreen)
{
WrapPanelBtn.Visibility = Visibility.Collapsed;
}
ScreenBorder.Visibility = Visibility.Hidden;
BitmapEncoder pngEncoder = new PngBitmapEncoder();
pngEncoder.Frames.Add(BitmapFrame.Create(CutBitmap()));
// ImageSource 转 Bitmap
System.Drawing.Bitmap bitmap = tools.ImageSourceToBitmap(pngEncoder.Frames[0]);
// Bitmap 转 BitmapImage
BitmapImage bitmapImage = tools.BitmapToBitmapImage(tools.GetPicThumbnail(bitmap,800,1270));
//BitmapImage 转 byte[]
byte[] buffer = tools.BitmapImageToByteArray(bitmapImage);
//清理资源
bitmapImage.StreamSource.Close();
bitmapImage.StreamSource.Dispose();
bitmapImage = null;
//保存为文件
tools.SaveFile(@"E:\1.png", buffer);
//UDP 发送
UDPSend.SendScreenFile(buffer);
GC.Collect();
this.Close();
break;
case "CancelBtn":
this.Close();
break;
default:
break;
}
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
}
/// <summary>
/// 裁剪图片
/// </summary>
/// <returns></returns>
private CroppedBitmap CutBitmap()
{
try
{
var renderTargetBitmap = new RenderTargetBitmap((int)DrawingBoard.Width, (int)DrawingBoard.Height, 96d, 96d, PixelFormats.Default);
renderTargetBitmap.Render(DrawingBoard);
return new CroppedBitmap(renderTargetBitmap, new Int32Rect((int)rect.X, (int)rect.Y, (int)rect.Width, (int)rect.Height));
}
catch (Exception ex)
{
WriteLog.WriteErrorInfo(ex);
}
return new CroppedBitmap();
}
}
}
