C#抓取当前屏幕并保存为图片的方法

using System;using System.Collections.Generic;using System.ComponentModel;using System.Diagnostics;using System.Drawing;using System.Drawing.Imaging;using System.IO;using System.Runtime.InteropServices;using System.Text;using System.Threading;using System.Windows.Forms;namespace RobvanderWoude{ class PrintScreen {  static int Main( string[] args )  {   try   {    string output = string.Empty;    bool overwrite = false;    bool text = false;    ImageFormat type = null;    #region Command Line parsing    if ( args.Length == 0 )    {     return WriteError( );    }    foreach ( string arg in args )    {     switch ( arg.ToUpper( ).Substring( 0, 2 ) )     {      case "/?":       return WriteError( );      case "/O":       overwrite = true;       break;      case "/T":       if ( text )       {        return WriteError( "Cannot capture current window as bitmap" );       }       switch ( arg.ToUpper( ).Substring( 3 ) )       {        case "BMP":         type = ImageFormat.Bmp;         break;        case "GIF":         type = ImageFormat.Gif;         break;        case "JPG":        case "JPEG":         type = ImageFormat.Jpeg;         break;        case "PNG":         type = ImageFormat.Png;         break;        case "TIF":        case "TIFF":         type = ImageFormat.Tiff;         break;        case "TXT":         text = true;         break;        default:         return WriteError( "Invalid file format: /"" + arg.Substring( 4 ) + "/"" );       }       break;      default:       output = arg;       break;     }    }    // Check if directory exists    if ( !Directory.Exists( Path.GetDirectoryName( output ) ) )    {     return WriteError( "Invalid path for output file: /"" + output + "/"" );    }    // Check if file exists, and if so, if it can be overwritten    if ( File.Exists( output ) )    {     if ( overwrite )     {      File.Delete( output );     }     else     {      return WriteError( "File exists; use /O to overwrite existing files." );     }    }    if ( type == null && text == false )    {     string ext = Path.GetExtension( output ).ToUpper( );     switch ( ext )     {      case ".BMP":       type = ImageFormat.Bmp;       break;      case ".GIF":       type = ImageFormat.Gif;       break;      case ".JPG":      case ".JPEG":       type = ImageFormat.Jpeg;       break;      case ".PNG":       type = ImageFormat.Png;       break;      case ".TIF":      case ".TIFF":       type = ImageFormat.Tiff;       break;      case ".TXT":       text = true;       break;      default:       return WriteError( "Invalid file type: /"" + ext + "/"" );       return 1;     }    }    #endregion Command Line parsing    if ( text )    {     string readtext = string.Empty;     for ( short i = 0; i < (short) Console.BufferHeight; i++ )     {      foreach ( string line in ConsoleReader.ReadFromBuffer( 0, i, (short) Console.BufferWidth, 1 ) )      {       readtext += line + "/n";      }     }     StreamWriter file = new StreamWriter( output );     file.Write( readtext );     file.Close( );    }    else    {     int width = Screen.PrimaryScreen.Bounds.Width;     int height = Screen.PrimaryScreen.Bounds.Height;     int top = 0;     int left = 0;     Bitmap printscreen = new Bitmap( width, height );     Graphics graphics = Graphics.FromImage( printscreen as Image );     graphics.CopyFromScreen( top, left, 0, 0, printscreen.Size );     printscreen.Save( output, type );    }    return 0;   }   catch ( Exception e )   {    Console.Error.WriteLine( e.Message );    return 1;   }  }  #region Error Handling  public static int WriteError( string errorMessage = "" )  {   Console.ResetColor( );   if ( string.IsNullOrEmpty( errorMessage ) == false )   {    Console.Error.WriteLine( );    Console.ForegroundColor = ConsoleColor.Red;    Console.Error.Write( "ERROR: " );    Console.ForegroundColor = ConsoleColor.White;    Console.Error.WriteLine( errorMessage );    Console.ResetColor( );   }   Console.Error.WriteLine( );   Console.Error.WriteLine( "PrintScreen, Version 1.10" );   Console.Error.WriteLine( "Save a screenshot as image or save the current console buffer as text" );   Console.Error.WriteLine( );   Console.Error.Write( "Usage:  " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.WriteLine( "PRINTSCREEN outputfile [ /T:type ] [ /O ]" );   Console.ResetColor( );   Console.Error.WriteLine( );   Console.Error.Write( "Where:  " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "outputfile" );   Console.ResetColor( );   Console.Error.WriteLine( "  is the file to save the screenshot or text to" );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "   /T:type" );   Console.ResetColor( );   Console.Error.Write( "  specifies the file type: " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "BMP" );   Console.ResetColor( );   Console.Error.Write( ", " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "GIF" );   Console.ResetColor( );   Console.Error.Write( ", " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "JPG" );   Console.ResetColor( );   Console.Error.Write( ", " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "PNG" );   Console.ResetColor( );   Console.Error.Write( ", " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "TIF" );   Console.ResetColor( );   Console.Error.Write( " or " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.WriteLine( "TXT" );   Console.ResetColor( );   Console.Error.Write( "      (only required if " );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "outputfile" );   Console.ResetColor( );   Console.Error.WriteLine( " extension is different)" );   Console.ForegroundColor = ConsoleColor.White;   Console.Error.Write( "   /O" );   Console.ResetColor( );   Console.Error.WriteLine( "    overwrites an existing file" );   Console.Error.WriteLine( );   Console.Error.Write( "Credits: Code to read console buffer by Simon Mourier " );   Console.ForegroundColor = ConsoleColor.DarkGray;   Console.Error.WriteLine( "http://www.sina.com.cn" );   Console.ResetColor( );   Console.Error.Write( "   Code for graphic screenshot by Ali Hamdar " );   Console.ForegroundColor = ConsoleColor.DarkGray;   Console.Error.WriteLine( "//www.VeVB.COm" );   Console.ResetColor( );   Console.Error.WriteLine( );   Console.Error.WriteLine( "Written by Rob van der Woude" );   Console.Error.WriteLine( "http://www.qq.com" );   return 1;  }  #endregion Error Handling } #region Read From Console Buffer public class ConsoleReader {  public static IEnumerable<string> ReadFromBuffer( short x, short y, short width, short height )  {   IntPtr buffer = Marshal.AllocHGlobal( width * height * Marshal.SizeOf( typeof( CHAR_INFO ) ) );   if ( buffer == null )    throw new OutOfMemoryException( );   try   {    COORD coord = new COORD( );    SMALL_RECT rc = new SMALL_RECT( );    rc.Left = x;    rc.Top = y;    rc.Right = (short) ( x + width - 1 );    rc.Bottom = (short) ( y + height - 1 );    COORD size = new COORD( );    size.X = width;    size.Y = height;    const int STD_OUTPUT_HANDLE = -11;    if ( !ReadConsoleOutput( GetStdHandle( STD_OUTPUT_HANDLE ), buffer, size, coord, ref rc ) )    {     // 'Not enough storage is available to process this command' may be raised for buffer size > 64K (see ReadConsoleOutput doc.)     throw new Win32Exception( Marshal.GetLastWin32Error( ) );    }    IntPtr ptr = buffer;    for ( int h = 0; h < height; h++ )    {     StringBuilder sb = new StringBuilder( );     for ( int w = 0; w < width; w++ )     {      CHAR_INFO ci = (CHAR_INFO) Marshal.PtrToStructure( ptr, typeof( CHAR_INFO ) );      char[] chars = Console.OutputEncoding.GetChars( ci.charData );      sb.Append( chars[0] );      ptr += Marshal.SizeOf( typeof( CHAR_INFO ) );     }     yield return sb.ToString( );    }   }   finally   {    Marshal.FreeHGlobal( buffer );   }  }  [StructLayout( LayoutKind.Sequential )]  private struct CHAR_INFO  {   [MarshalAs( UnmanagedType.ByValArray, SizeConst = 2 )]   public byte[] charData;   public short attributes;  }  [StructLayout( LayoutKind.Sequential )]  private struct COORD  {   public short X;   public short Y;  }  [StructLayout( LayoutKind.Sequential )]  private struct SMALL_RECT  {   public short Left;   public short Top;   public short Right;   public short Bottom;  }  [StructLayout( LayoutKind.Sequential )]  private struct CONSOLE_SCREEN_BUFFER_INFO  {   public COORD dwSize;   public COORD dwCursorPosition;   public short wAttributes;   public SMALL_RECT srWindow;   public COORD dwMaximumWindowSize;  }  [DllImport( "kernel32.dll", SetLastError = true )]  private static extern bool ReadConsoleOutput( IntPtr hConsoleOutput, IntPtr lpBuffer, COORD dwBufferSize, COORD dwBufferCoord, ref SMALL_RECT lpReadRegion );  [DllImport( "kernel32.dll", SetLastError = true )]  private static extern IntPtr GetStdHandle( int nStdHandle ); } #endregion Read From Console Buffer}