Parameters
- fileId
- A file identifier.
- pageIndex
- A zero-based image index in source image file.
- thumbnailSize
- Thumbnail size in pixels.
- encoder
- The encoder used to work with thumbnails.
Return Value
Thumbnail identifier.
Target Platforms: .NET 11; .NET 10; .NET 9; .NET 8; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5