ScreenCaptureEngine Class

Summary
The main class for the Screen Capture Engine.
Syntax
C#
VB
C++
public class ScreenCaptureEngine : IDisposable 
  
Public Class ScreenCaptureEngine  
   Implements System.IDisposable  
public ref class ScreenCaptureEngine : public System.IDisposable   
Example

Defines screen capture structures, and class objects, captures an area of the screen, and then counts the number of resources in an EXE file

C#
VB
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ScreenCapture; 
 
public void ScreenCaptureEngineExample() 
{ 
   // Startup the ScreenCapture 
   ScreenCaptureEngine.Startup(); 
 
   // Define a ScreenCaptureEngine class object 
   ScreenCaptureEngine scEngine = new ScreenCaptureEngine(); 
 
   // Define an EventHandler for CaptureInformation 
   scEngine.CaptureInformation += new EventHandler<ScreenCaptureInformationEventArgs>(scEngine_CaptureInformation); 
 
   // Define the Help Callback that will run whenever the Help button is pressed on the dialogs 
   ScreenCaptureHelpCallback helpCallback = new ScreenCaptureHelpCallback(HelpCallback); 
 
   // Define ScreenCaptureAreaOptions and fill it using dialog 
   ScreenCaptureAreaOptions scAreaOptions = ScreenCaptureAreaOptions.Empty; 
   // Get the default options 
   scAreaOptions = ScreenCaptureEngine.DefaultCaptureAreaOptions; 
   // Open the dialog allowing the user to change the values 
   // NOTE: To fill the structure manually, you can write: 
   // Cursor drawCursor = Cursors.Cross; 
   // scAreaOptions.AreaType = ScreenCaptureAreaType.Rectangle; 
   // scAreaOptions.DrawCursor = drawCursor; 
   // scAreaOptions.DrawLineColor = Color.Red; 
   // scAreaOptions.DrawLineStyle = ScreenCaptureAreaLineStyle.Solid; 
   // scAreaOptions.EllipseHeight = 0; 
   // scAreaOptions.EllipseWidth = 0; 
   // scAreaOptions.FillBackgroundColor = Color.Black; 
   // scAreaOptions.FillForegroundColor = Color.White; 
   // scAreaOptions.FillPattern = ScreenCaptureAreaFillPattern.Solid; 
   // scAreaOptions.Flags = ScreenCaptureAreaFlags.ShowInfoWindow; 
   // scAreaOptions.InfoWindowBounds = new Rectangle(ScreenCaptureAreaOptions.LeftInfoWindowPosition, ScreenCaptureAreaOptions.TopInfoWindowPosition, ScreenCaptureAreaOptions.MediumInfoWindowSize, ScreenCaptureAreaOptions.MediumInfoWindowSize); 
   // scAreaOptions.TextBackgroundColor = Color.White; 
   // scAreaOptions.TextForegroundColor = Color.Black; 
   // scAreaOptions.Zoom = ScreenCaptureAreaZoom.Normal; 
   scEngine.ShowCaptureAreaOptionsDialog(null, ScreenCaptureDialogFlags.CaptureAreaOptionsContextHelp, scAreaOptions, true, helpCallback); 
 
   // Define ScreenCaptureOptions and fill it using dialog 
   ScreenCaptureOptions scOptions = ScreenCaptureOptions.Empty; 
   // Set the ScreenCaptureHotKeyCallback, so that it gets called if the hotkey is set in the dialog 
   ScreenCaptureHotkeyCallback hotkeyCallback = new ScreenCaptureHotkeyCallback(HotKeyCallback); 
   ScreenCaptureEngine.SetCaptureHotkeyCallback(hotkeyCallback); 
   // Open the dialog allowing the user to change the values 
   // NOTE: To fill the structure manually, you can write: 
   // scOptions.CancelKey = Keys.Escape; 
   // scOptions.Count = 1; 
   // scOptions.Cursor = Cursors.Arrow; 
   // scOptions.Delay = 0; 
   // scOptions.Hotkey = Keys.F11; 
   // scOptions.Interval = 0; 
   // scOptions.OptimizedHotkey = true; 
   // scOptions.StatusCursor = Cursors.WaitCursor; 
   scEngine.ShowCaptureOptionsDialog(null, ScreenCaptureDialogFlags.SetCaptureOptionsContextHelp, scOptions, helpCallback); 
   // Set the Engine's ScreenCaptureOptions 
   scEngine.CaptureOptions = scOptions; 
 
   // Define ScreenCaptureObjectOptions and fill it using dialog 
   ScreenCaptureObjectOptions scObjectOptions = ScreenCaptureObjectOptions.Empty; 
   // Get the default Options 
   scObjectOptions = ScreenCaptureEngine.DefaultCaptureObjectOptions; 
   // Open the dialog allowing the user to change the values 
   // NOTE: To fill the structure manually, you can write: 
   // scObjectOptions.BorderWidth = 2; 
   // scObjectOptions.EnableKeyboard = true; 
   // scObjectOptions.Invert = false; 
   // scObjectOptions.SelectCursor = Cursors.Arrow; 
   scEngine.ShowCaptureObjectOptionsDialog(null, ScreenCaptureDialogFlags.CaptureObjectOptionsContextHelp, scObjectOptions, true, helpCallback); 
 
   // Define ScreenCaptureInformation class object 
   ScreenCaptureInformation scInformation = null; 
 
   // NOTE: After preparing the structures and classes, 
   // in this place you can insert any Capture method, such as: 
   // CaptureWindow, CaptureActiveWindow, CaptureActiveClient, CaptureWallpaper, 
   // CaptureFullScreen, CaptureMenuUnderCursor, CaptureWindowUnderCursor, 
   // CaptureSelectedObject, CaptureArea, CaptureMouseCursor 
 
   // We will Capture an Area of the screen 
   RasterImage image = scEngine.CaptureArea(scAreaOptions, scInformation); 
 
   // To get the number of resources in a EXE file 
   int iconsCount = scEngine.GetResourcesCount(Path.Combine(LEAD_VARS.ImagesDir, "ExeWithResources.exe"), ScreenCaptureResourceType.Icon); 
 
   // Finally, if the Capture is still active, then Stop it 
   if (scEngine.IsCaptureActive) 
      scEngine.StopCapture(); 
 
   // clean up 
   image.Dispose(); 
 
   // Shutdown the ScreenCapture 
   ScreenCaptureEngine.Shutdown(); 
} 
 
bool HotKeyCallback(Keys key) 
{ 
   // Here you can do anything with the pressed key 
   // we will just show a message box 
   MessageBox.Show("You pressed the " + key.ToString() + "character."); 
 
   return true; 
} 
 
void HelpCallback(ScreenCaptureHelpType helpType, ScreenCaptureControlId controlId) 
{ 
   // Show a MessageBox mentioning the name of the dialog that called the help, 
   // and which control ID was requested. 
   switch (helpType) 
   { 
      case ScreenCaptureHelpType.CaptureAreaOptions: 
         MessageBox.Show("Capture Area Options Dialog Help Button\n" + 
            "Control Id: " + controlId.ToString() + "."); 
         break; 
      case ScreenCaptureHelpType.CaptureFromExe: 
         MessageBox.Show("Capture From EXE Dialog Help Button\n" + 
            "Control Id: " + controlId.ToString() + "."); 
         break; 
      case ScreenCaptureHelpType.CaptureObjectOptions: 
         MessageBox.Show("Capture Object Options Dialog Help Button\n" + 
            "Control Id: " + controlId.ToString() + "."); 
         break; 
      case ScreenCaptureHelpType.SetCaptureOptions: 
         MessageBox.Show("Capture Options Dialog Help Button\n" + 
            "Control Id: " + controlId.ToString() + "."); 
         break; 
      default: 
         // will never reach here 
         break; 
   } 
} 
 
void scEngine_CaptureInformation(object sender, ScreenCaptureInformationEventArgs e) 
{ 
   // Make sure that the image was captured successfully 
   Debug.Assert(e.Image != null); 
 
   // Define codecs class object to save the image 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   // Save the resulted Image 
   codecs.Save(e.Image, Path.Combine(LEAD_VARS.ImagesDir, "Out_CapturedImage.bmp"), RasterImageFormat.Bmp, 24); 
 
 
   // NOTE: e.Information is a ScreenCaptureInformation structure filled with information 
   // about the captured image, this information can be used here 
   // Display a MessageBox with the bounds of the capture area 
   MessageBox.Show("Captured Area Bounds:\n" + 
      "Top:" + e.Information.Area.Top.ToString() + "\n" + 
      "Left:" + e.Information.Area.Left.ToString() + "\n" + 
      "Right:" + e.Information.Area.Right.ToString() + "\n" + 
      "Bottom:" + e.Information.Area.Bottom.ToString()); 
 
   // everything worked fine 
   e.Cancel = false; 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 
} 
Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ScreenCapture 
 
WithEvents scEngine As ScreenCaptureEngine 
Public Sub ScreenCaptureEngineExample() 
   ' Startup the ScreenCapture 
   ScreenCaptureEngine.Startup() 
 
   ' Define a ScreenCaptureEngine class object 
   scEngine = New ScreenCaptureEngine() 
 
   ' Define the Help Callback that will run whenever the Help button is pressed on the dialogs 
   Dim helpCallbackObj As New ScreenCaptureHelpCallback(AddressOf HelpCallback) 
 
   ' Define ScreenCaptureAreaOptions and fill it using dialog 
   Dim scAreaOptions As ScreenCaptureAreaOptions 
   scAreaOptions = ScreenCaptureAreaOptions.Empty 
 
   ' Get the default options 
   scAreaOptions = ScreenCaptureEngine.DefaultCaptureAreaOptions 
 
   ' Open the dialog allowing the user to change the values 
   ' NOTE: To fill the structure manually, you can write: 
   ' Cursor drawCursor = Cursors.Cross; 
   ' scAreaOptions.AreaType = ScreenCaptureAreaType.Rectangle; 
   ' scAreaOptions.DrawCursor = drawCursor; 
   ' scAreaOptions.DrawLineColor = Color.Red; 
   ' scAreaOptions.DrawLineStyle = ScreenCaptureAreaLineStyle.Solid; 
   ' scAreaOptions.EllipseHeight = 0; 
   ' scAreaOptions.EllipseWidth = 0; 
   ' scAreaOptions.FillBackgroundColor = Color.Black; 
   ' scAreaOptions.FillForegroundColor = Color.White; 
   ' scAreaOptions.FillPattern = ScreenCaptureAreaFillPattern.Solid; 
   ' scAreaOptions.Flags = ScreenCaptureAreaFlags.ShowInfoWindow; 
   ' scAreaOptions.InfoWindowBounds = new Rectangle(ScreenCaptureAreaOptions.LeftInfoWindowPosition, ScreenCaptureAreaOptions.TopInfoWindowPosition,_  
   ' ScreenCaptureAreaOptions.MediumInfoWindowSize, ScreenCaptureAreaOptions.MediumInfoWindowSize); 
   ' scAreaOptions.TextBackgroundColor = Color.White; 
   ' scAreaOptions.TextForegroundColor = Color.Black; 
   ' scAreaOptions.Zoom = ScreenCaptureAreaZoom.Normal; 
   scEngine.ShowCaptureAreaOptionsDialog(Nothing, ScreenCaptureDialogFlags.CaptureAreaOptionsContextHelp, scAreaOptions, True, helpCallbackObj) 
 
   ' Define ScreenCaptureOptions and fill it using dialog 
   Dim scOptions As ScreenCaptureOptions 
   scOptions = ScreenCaptureOptions.Empty 
 
   ' Set the ScreenCaptureHotKeyCallback, so that it gets called if the hotkey is set in the dialog 
   Dim hotkeyCallbackObj As New ScreenCaptureHotkeyCallback(AddressOf HotKeyCallback) 
   ScreenCaptureEngine.SetCaptureHotkeyCallback(hotkeyCallbackObj) 
 
   ' Open the dialog allowing the user to change the values 
   ' NOTE: To fill the structure manually, you can write: 
   ' scOptions.CancelKey = Keys.Escape; 
   ' scOptions.Count = 1; 
   ' scOptions.Cursor = Cursors.Arrow; 
   ' scOptions.Delay = 0; 
   ' scOptions.Hotkey = Keys.F11; 
   ' scOptions.Interval = 0; 
   ' scOptions.OptimizedHotkey = true; 
   ' scOptions.StatusCursor = Cursors.WaitCursor; 
   scEngine.ShowCaptureOptionsDialog(Nothing, ScreenCaptureDialogFlags.SetCaptureOptionsContextHelp, scOptions, helpCallbackObj) 
 
   ' Set the Engine's ScreenCaptureOptions 
   scEngine.CaptureOptions = scOptions 
 
   ' Define ScreenCaptureObjectOptions and fill it using dialog 
   Dim scObjectOptions As ScreenCaptureObjectOptions 
   scObjectOptions = ScreenCaptureObjectOptions.Empty 
 
   ' Get the default Options 
   scObjectOptions = ScreenCaptureEngine.DefaultCaptureObjectOptions 
 
   ' Open the dialog allowing the user to change the values 
   ' NOTE: To fill the structure manually, you can write: 
   ' scObjectOptions.BorderWidth = 2; 
   ' scObjectOptions.EnableKeyboard = true; 
   ' scObjectOptions.Invert = false; 
   ' scObjectOptions.SelectCursor = Cursors.Arrow; 
   scEngine.ShowCaptureObjectOptionsDialog(Nothing, ScreenCaptureDialogFlags.CaptureObjectOptionsContextHelp, scObjectOptions, True, helpCallbackObj) 
 
   ' Define ScreenCaptureInformation class object 
   Dim scInformation As ScreenCaptureInformation = Nothing 
 
   ' NOTE: After preparing the structures and classes, 
   ' in this place you can insert any Capture method, such as: 
   ' CaptureWindow, CaptureActiveWindow, CaptureActiveClient, CaptureWallpaper, 
   ' CaptureFullScreen, CaptureMenuUnderCursor, CaptureWindowUnderCursor, 
   ' CaptureSelectedObject, CaptureArea, CaptureMouseCursor 
 
   ' We will Capture an Area of the screen 
   Dim image As RasterImage 
   image = scEngine.CaptureArea(scAreaOptions, scInformation) 
 
   ' To get the number of resources in a EXE file 
   Dim iconsCount As Integer 
 
   iconsCount = scEngine.GetResourcesCount(Path.Combine(LEAD_VARS.ImagesDir, "ExeWithResources.exe"), ScreenCaptureResourceType.Icon) 
 
   ' Finally, if the Capture is still active, then Stop it 
   If (scEngine.IsCaptureActive) Then 
      scEngine.StopCapture() 
   End If 
 
   ' clean up 
   image.Dispose() 
 
   ' Shutdown the ScreenCapture 
   ScreenCaptureEngine.Shutdown() 
End Sub 
 
Public Function HotKeyCallback(ByVal key As Keys) As Boolean 
   ' Here you can do anything with the pressed key 
   ' we will just show a message box 
   MessageBox.Show("You pressed the " + key.ToString() + "character.") 
 
   Return True 
End Function 
 
Public Sub HelpCallback(ByVal helpType As ScreenCaptureHelpType, ByVal controlId As ScreenCaptureControlId) 
   ' Show a MessageBox mentioning the name of the dialog that called the help, 
   ' and which control ID was requested. 
   Select Case (helpType) 
      Case ScreenCaptureHelpType.CaptureAreaOptions 
         MessageBox.Show("Capture Area Options Dialog Help Button" & Environment.NewLine & "Control Id: " & controlId.ToString() & ".") 
      Case ScreenCaptureHelpType.CaptureFromExe 
         MessageBox.Show("Capture From EXE Dialog Help Button" & Environment.NewLine & "Control Id: " & controlId.ToString() & ".") 
      Case ScreenCaptureHelpType.CaptureObjectOptions 
         MessageBox.Show("Capture Object Options Dialog Help Button" & Environment.NewLine & "Control Id: " & controlId.ToString() & ".") 
      Case ScreenCaptureHelpType.SetCaptureOptions 
         MessageBox.Show("Capture Options Dialog Help Button" & Environment.NewLine & "Control Id: " & controlId.ToString() & ".") 
      Case Else 
         ' will never reach here 
   End Select 
End Sub 
 
Public Sub scEngine_CaptureInformation(ByVal sender As Object, ByVal e As ScreenCaptureInformationEventArgs) Handles scEngine.CaptureInformation 
 
   ' Define codecs class object to save the image 
   Dim codecs As New RasterCodecs() 
   codecs.ThrowExceptionsOnInvalidImages = True 
 
   ' Save the resulted Image 
   codecs.Save(e.Image, Path.Combine(LEAD_VARS.ImagesDir, "CapturedImage.bmp"), RasterImageFormat.Bmp, 24) 
 
 
   ' NOTE: e.Information is a ScreenCaptureInformation structure filled with information 
   ' about the captured image, this information can be used here 
   ' Display a MessageBox with the bounds of the capture area 
   MessageBox.Show("Captured Area Bounds:" & Environment.NewLine & "Top:" & e.Information.Area.Top.ToString() & Environment.NewLine & 
                   "Left:" & e.Information.Area.Left.ToString() & Environment.NewLine & "Right:" + e.Information.Area.Right.ToString() & 
                   Environment.NewLine & "Bottom:" & e.Information.Area.Bottom.ToString()) 
 
   ' everything worked fine 
   e.Cancel = False 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
End Class 
Requirements

Target Platforms

Help Version 21.0.2021.6.30
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© 1991-2021 LEAD Technologies, Inc. All Rights Reserved.

Leadtools.ScreenCapture Assembly

Products | Support | Contact Us | Intellectual Property Notices
© 1991-2021 LEAD Technologies, Inc. All Rights Reserved.