TwainOpenDefaultSource Method

See Also Examples Applies To

This opens the source selected in the Select Source dialog.
If some source is already open, does nothing and returns TRUE.
First call this function for each scanning process or to set the TWAIN state to 4 (TWAIN_SOURCE_OPEN) when the TWAIN state is 3 (TWAIN_SM_OPEN) or 2 (TWAIN_SM_LOADED) or 1 (TWAIN_PRESESSION).

Syntax

object.TwainOpenDefaultSource ()

The TwainOpenDefaultSource syntax has these parts:

Part	Description
object	Required. An object expression that evaluates to an object in the Applies To list.

Returns

Boolean. True if success, else False -> Use TwainGetLastResultCode() and TwainGetLastConditionCode() functions for diagnosing the error.

Remarks

If this call returns TRUE, TWAIN is in STATE 4 (TWAIN_SOURCE_OPEN).

Category

TWAIN Functions

Visual Basic Sample

Acquire multiple image from the document feeder to a multipage PDF


Dim nImageID As Long

Object.TwainOpenDefaultSource
Object.TwainSetAutoFeed (True) 'Enable AutoFeed
Object.TwainSetAutoScan (True) 'To  achieve the maximum scanning rate
Object.TwainSetCurrentPixelType (TWPT_RGB) '24 bit color image
Object.TwainEnableDuplex (True) 'Duplex acquisition if supported
Object.TwainSetHideUI (True) 'Asks to the device to hide his GUI

Call Object.TwainPdfStartEx("acquire.pdf", "PdfTitle", "PdfCreator", "PdfAuthor", "PdfProducer")
Do
  nImageID = Object.TwainAcquireToGdPictureImage(Me.hwnd)
  If nImageID <> 0 Then
     Object.TwainAddGdPictureImageToPdf (nImageID)
     Object.CloseImage (nImageID)
  End If
Loop While Object.TwainGetState() > 5

Object.TwainPdfStop
Object.TwainCloseSource

Acquire multiple image from the document feeder to a multipage tif image


Dim nImageID As Long
Dim nImageCount As Long

Object.TwainOpenDefaultSource
Object.TwainSetAutoFeed (True) 'Enable AutoFeed
Object.TwainSetAutoScan (True) 'To  achieve the maximum scanning rate
Object.TwainSetCurrentPixelType (TWPT_BW) '1 bit bw image
Object.TwainEnableDuplex (True) 'Duplex acquisition if supported
Object.TwainSetHideUI (True) 'Asks to the device to hide his GUI

nImageCount = 0
Do
  nImageID = Object.TwainAcquireToGdPictureImage(Me.hwnd)
  If nImageID <> 0 Then
     nImageCount = nImageCount + 1
     If nImageCount = 1 Then
        Call Object.TiffSaveAsNativeMultiPage("acquire.tif", CompressionCCITT4)
     Else
        Object.TiffAddToNativeMultiPage (nImageID)
     End If
     Object.CloseImage (nImageID)
  End If
Loop While Object.TwainGetState() > 5

Object.TiffCloseNativeMultiPage
Object.TwainCloseSource