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TwainUserInterfaceFlags Enumeration
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Leadtools.Twain Namespace : TwainUserInterfaceFlags Enumeration



Indicates whether to display the manufacturer's user interface.

Syntax

Visual Basic (Declaration) 
<FlagsAttribute()>
Public Enum TwainUserInterfaceFlags 
   Inherits Enum
Visual Basic (Usage)Copy Code
Dim instance As TwainUserInterfaceFlags
C# 
[FlagsAttribute()]
public enum TwainUserInterfaceFlags : Enum
C++/CLI 
[FlagsAttribute()]
public enum class TwainUserInterfaceFlags : public Enum

Members

MemberDescription
None Default, no user interface is shown. Not all TWAIN Data Sources support this feature.
Show Shows the manufacturer's user interface as modeless.
Modal Shows the manufacturer's user interface as a modal dialog. Works only if the Show is set.
KeepOpen Keep the TWAIN data source open after scanning.

The TwainUserInterfaceFlags.KeepOpen flag works only in the following cases:

  • Passed along with TwainUserInterfaceFlags.Show flag to make TWAIN user-interface appears as modeless dialog. The TWAIN data source remains open after scanning until the user closes it.
  • Passed along with TwainUserInterfaceFlags.Show and TwainUserInterfaceFlags.Modal flags to make the TWAIN user-interface appears as modal dialog. The TWAIN data source remains open after scanning until the user closes it.

MemoryCheckImageInfo Checks image information while scanning multi pages with different dimensions. This flag is used only with memory transfer mode.

Use MemoryCheckImageInfo flag only when memory transfer mode is used. Also, this flag will not affect native and file transfer modes.

When scanning multi pages or multi areas with memory transfer mode, you may need to use (MemoryCheckImageInfo); this flag will let the TWAIN DLL to check the image information for each page or area before start pending the image data to application.

Some drivers will not work with this flag like TWAIN Virtual Driver; in this case, you shouldn’t pass this flag.

The usage of the flag does not follow the TWAIN specification, but is included as work around for TWAIN drivers that scan multiple pages with different image dimensions. Usage of this flag should be limited only to these special and unusual cases.

ImageSizeUndefined Calculate the acquired image size after the image is acquired. This flag is used only with memory transfer mode.

Use ImageSizeUndefined flag only when memory transfer mode is used. So, to use this flag, you should set TwainCapabilityType.ImageTransferMechanism capability to TwainTransferMechanism.Memory and then set TwainCapabilityType.ImageUndefinedImageSize capability to TRUE before calling TwainSession.Acquire(), otherwise, the TwainSession.Acquire() will return an error.

Inheritance Hierarchy

System.Object
   System.ValueType
      System.Enum
         Leadtools.Twain.TwainUserInterfaceFlags

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also