PdfViewer: Blank Thumbnails

[aweidner]

Hello,

I have just built a simple PDF viewer in a .NET Forms application.

In the first version of the program, the form did only contain a PdfDocumentViewer element. Loading a PDF file into this control displayed the contents of the PDF file in the control. Everything okay.

In the second version, I have added a second control, a PdfDocumentThumbnail and habe linked this to the PdfDocumentViewer control via it's "Viewer" property.

Upon loading the PDF file into the PdfDocumentViewer control, the PdfDocumentThumbnail control shows as many icons as there are pages in the sample PDF file, but all the preview icons are blank. Moreover, the pages displayed in the PdfDocumentViewer control are also just blank pages. The contents which has been displayed correctly in the first version of the program is all gone.

Is there anything that can be done to rod of this strange behaviour or do you have any code snippet that's working correctly?

Regards,

Axel Weidner

[nancy.yang]

Hello,

Thank you for your inquiry.
After an initial test with the latest Spire.PDFViewer Pack(Hotfix) Version:4.2.2, I didn’t encounter your issue. If you are using an older version, please try it with the new version, If your problem still occurs after trying, we need the following information to do an accurate investigation. Please share them with us. You can send it to us via email (support@e-iceblue.com). Thanks in advance.
1. You input Pdf document.
2. Your project.
3. The VS version you used such as VS 2017.

Sincerely,
Nancy
E-iceblue support team

[aweidner]

Hello Nancy,

I had downloaded PdfViewer via NuGet in VS 2019 a couple of days ago and it says it's Version 4.2.2. Nevertheless, I would like to install the most recent patch you have linked in your post. How is the patch to be installed (which files go into which directories?). Is there an installation routine available for the patch?

After having the patch properly installed I will give the test application another try and Keep you informed about the behaviour.

Kind regards

Axel Weidner

[aweidner]

Hello Nancy,

I just checked the PdfViewer Version by invoking the ProductVersion Property of the PdfDoumentViewer instance. The result was 4.2.2.3046.

As you have stated in your post that 4.2.2 ist the most recent version, I assume that it's not neccessary to update the product. Seems to be some kind of irregular behaviour of the PdfViewer implementation. I will upload a code sample some time during the next two days.

Kind regards,

Axel Weidner

[aweidner]

Hello Nancy,

please find enclosed the test application which can be used to test the misbehaviour of the PdfViewer Class that I have descri8bed in my initial post.

Kind regards,

Axel Weidner

[nancy.yang]

Hi,

Thank you for your feedback.
Sorry I didn’t find your enclosed application in this post. Please kindly note that our forums has the size limitation for attachment. You could upload your application via OneDrive or Dropbox, and then share us with the link to download or you can send the link to our email(support@e-iceblue.com). Thanks in advance.

Sincerely,
Nancy
E-iceblue support team

[aweidner]

Hello Nancy,

due to data protection and IT safety regulations, we are not allowed to use Dropbox or any other similar service. I can provide you with the source code for the application. I assume thsi Archive file file will be small enough for a upload via this Forum. If you need additional files, I might transfer them via FTP, for example. Sending larger files as E-Mail attachments is another Option, but public services like dropbox or any other online storage service is not an Option and will be blocked by our security systems.

Kind regards,

Axel Weidner

[nancy.yang]

Hello,

Thanks for your feedback.
I understood your situation, but you have no need to worry about it, we take customers’ confidential information as seriously as them. We will never publish or disclose any information of our customer. This is always the promise we keep to our customer and the regulation we must obey. Anyway, Here I uploaded my testing application for your reference, please run it and test your input PDF file. If there is any question, please provide your input PDF as well as the screenshot of your issues to help us further look into it. You could send them to us via email(support@e-iceblue.com).

Sincerely,
Nancy
E-iceblue support team

[aweidner]

Hello Nancy,

thank you for your refernce implementation. I just ran the code in VS 2019 and it behaves exctly as my own application and displays just white pages as thumbnails and in the viewer control.

Please find a screenshot of the appication's behaviour enclosed.


Kind regards,

Axel Weidner

TestApplication.JPG

[nancy.yang]

Hi,

Thanks for your quick feedback.
How about the result when you test my input PDF (“Test.pdf”)? I am afraid your issue should be related to your input file. To help us look into your issue quickly and accurately, please provide your input Pdf document as well as your testing environment (system configuration. E.g. Windows 7 64-bit, and region setting E.g. China, Chinese.). You could send them to us via email (support@e-iceblue.com). And don’t worry, we promise to keep your resources confidential and won’t use them for other purpose. You can remove sensitive information from your document, just make sure the modified file can reproduce your issue. Thanks in advance.

Sincerely,
Nancy
E-iceblue support team

[aweidner]

TestApplication-2.JPG

Hello Nancy,

running your test application with the sample PDF file you had enclosed doesn't Change anything. Both the Thumbnail conrol and the Viewer control Show nothing but blank pages.

The System is a virtualized Win 10 1709 Environment, running on a HPE DL380 Gen9 Server. Virtual Memory for the VM is 8 GB, OS fully patched and updated, running the new VS 2019 IDE. All settings specific to language, keyboard, charsets and location are set to German as this is the configuration that's being used for the end user systems also.
By the way, I tried to compile both our test applications (yours and mine) with VS 2017 and this didn't change the behaviour by the least bit.

There is one question: As far as I've seen, PdfViewer also ist ist loading Spire.PDF as a library. Might it be possible that PDFViewer is loading an old and outdated version of the Spire.PDF DLL? Is there any way to find this out? Maybe the Sysinterals Tools might be helpful, I assume.

Kind regards,

Axel Weidner

TestApplication-2.JPG

[nancy.yang]

Hi,

Thanks for your quick feedback.
When setting the region as German/ Germany, I have reproduced your issue and submitted it to our Dev team for further investigating and fixing. If there is any update, we will let you know. Sorry for the inconvenience caused.

Sincerely,
Nancy
E-iceblue support team

[aweidner]

Hello Nancy,

I just wanted to ask if you can provide me with a bug fix for the abovementioned problem.

We have halted the development process for a couple of days and most probably we will be able to continue doing so for a few more days but we have to continue with our development work ASAP because we have to keep up with a fixed project timeline.

Please inform me in case your develeopment team will not be able to provide a fix in a very short time. In this case we will stop developing for Spire PdfViewer and will subsequently change over to some other PDF library.


Kind regards,

Axel Weidner

[nancy.yang]

Dear Alex,

Sorry your issue has not been resolved yet. Our Dev team is still working on it and I'm afraid I can't provide an accurate timeline to you at this moment. Nevertheless, I have given your issue a high priority and requested our Dev team to share any possible ETA at their earliest. Once there is any available update, I will notify you. Thanks for your cooperation.

Sincerely,
Nancy
E-iceblue support team

[nancy.yang]

Hi,

Thanks for your patient waiting.
Glad to inform you that the reported issue has been resolved, welcome to download the hotfix from the following link.
Website link: Spire.PDFViewer Pack Version:4.5

Sincerely,
Nancy
E-iceblue support team