Declaration
procedure Update();
Description
Ensures that the current Twain properties are valid.
For example, if the application assigns a combination of
PixelType and
YResolution unsupported by scanner, the Update method restores the PixelType and YResolution value to a value supported by the scanner.
Note: Don't use this method to refresh the list of available devices, use
SetDefaultParams instead.
// Try if RGB and YResolution combination is supported
ImageEnView1.IO.TwainParams.PixelType.CurrentValue := 2;
ImageEnView1.IO.TwainParams.YResolution.CurrentValue := 300;
ImageEnView1.IO.TwainParams.Update();
if (ImageEnView1.IO.TwainParams.PixelType.CurrentValue<>2) or (ImageEnView1.IO.TwainParams.YResolution.CurrentValue<>300) then
ShowMessage('error!');