Capture/Image Source

Can the Dynamic Web TWAIN SDK detect whether papers exist on the flatbed?

Yes. You can use IfFeederLoaded API to inspect whether papers are loaded in the feeder of your current scanner. Before calling this API, please use IfPaperDetectable to inspect whether your current scanner hardware has a sensor to detect papers.

Code Example:

DWObject.SelectSource();
DWObject.OpenSource();
if(DWObject.IfPaperDetectable)
  if(DWObject.IfFeederLoaded)
    DWObject.AcquireImage();
  else
    alert("There is no paper in the feeder.");
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