By default, the ThumbnailType property is exThumbnailAvail. 

If the ThumbnailType property is exThumbnailAvail the control checks: 

• if the InputFile property points to a picture file, loads directly the picture from, and so the ThumbnailType property retrieves the exThumbnailPicture
• else, if the InputFile has a bitmap representation, the the ThumbnailType property retrieves the exThumbnailBitmap
• else, the ThumbnailType property retrieves the exThumbnailIcon

Use the ThumbnailType property to specify whether the thumbnail is a picture, bitmap or an icon. Use the Thumbnail property to retrieve the thumbnail picture. Use the InputFile property to programmatically display a thumbnail for a specified file. Use the OutputFile property to save the thumbnail picture. For instance, if you set the ThumbnailType property on exThumbnailIcon, and calling the InputFile property, the control gets the icon representation of the file. If the ThumbnailType property on exThumbnailIcon is exThumbnailBitmap the control tries to get a bitmap representation of the file if it is available, else the Thumbnail property is nothing, and the ThumbnailType property is exNoThumbnail.

Let's say that we drop the floppy.png file to the component, and based on the ThumbnailType property the component generates the following views:

1. exThumbnailPicture (The thumbnail type is a bitmap, but the original file is a picture being loaded directly)

   

2. exThumbnailBitmap (The thumbnail type is a bitmap)

   

3. exThumbnailIcon (The thumbnail type is an icon.)