Hi, I’m trying to create PDF documents using Aspose.Pdf (C#/.NET), Version=19.5.0.0.
There’s an intermittent problem where sometimes the PDF generated is blank.
I’ve tried viewing the PDF in Notepad++ and can’t seem to find a pattern.
Here is what the blank pdf looks like in Adobe Acrobat Reader DC for both examples below:
image.png (19.0 KB)
Example 1:
In this example, the blank pdf is 420KB, 2 pages long, and the non-blank pdf is 424KB and 2 pages long.
Here is a file comparison:
The blank PDF is on the left and the equivalent non-blank pdf is on the right.
image.png (8.6 KB)
image.png (11.3 KB)
image.png (7.8 KB)
image.png (126.4 KB)
image.png (135.7 KB)
image.png (66.8 KB)
image.png (21.1 KB)
image.png (20.9 KB)
To fix the blank pdf, all I had to do was add “trailer” on the line above the line that has “trailer” already there:
image.png (3.1 KB)
Example 2:
In this example, the blank pdf is 424KB, 2 pages long, and the non-blank pdf is 400KB and 2 pages long.
Here is a file comparison:
The blank PDF is on the left and the equivalent non-blank pdf is on the right.
image.png (24.5 KB)
image.png (54.2 KB)
image.png (25.9 KB)
image.png (21.9 KB)
image.png (107.8 KB)
image.png (19.7 KB)
image.png (58.0 KB)
image.png (26.4 KB)
image.png (5.3 KB)
In this example, I removed lines 3322 to 3563 and it fixed the blank pdf.
Why does a blank PDF get generated intermittently?
If there is no fix for this, is there a way to determine whether or not the pdf is blank from analysing the binary programmatically?