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Groups docs Viewer for .Net - Document rendering as original

Dear All,

We are checking with .Net version of the viewer and wants to render the document as original format (pdf) but my understanding is groupdocs converts every format to image and then render in the viewer
Following are the questions
1.Can we use the viewer without converting the original document to images like pdf to be rendered as pdf only.
2.Even if it cant render pdf in its original file format . Does search work for any text within the rendered file in viewer.



Thanks for taking interest in GroupDocs.Viewer.

First of all, it is important to tell you that GroupDocs.Viewer is a back-end, UI less API that allows you to render the document in the form that can be easily displayable in the front-end applications. Currently, the API provides Html based rendering and image-based rendering of the supported document formats. Furthermore, it also allows you to render the document as PDF document.

  • HTML based rendering: In HTML based rendering, the API generates the HTML representation of each page of the source document. You can easily manipulate the HTML content of each page and save it as an HTML file. For details, please visit Rendering Documents as HTML.
  • Image-based rendering: In image-based rendering, the API converts each page of the document into an image (PNG, JPG, BMP). You can easily save the image to your desired location and display it in your application to view the content of the document. For details, please visit Rendering Documents as Image.

As the API provides the back-end features of document rendering and it does not contain any built-in viewer control, therefore, you will have to create your own front end application to display the rendered Html pages or images.

We have also developed open source document viewer applications (listed below) using GroupDocs.Viewer for .NET that will help you understand the working of the API. You can also use these applications and modify them as per your requirements.

Yes, you can get the PDF as its original format using GroupDocs.Viewer (see this). However, you can not view/display the document in its original format directly in your front end application. The document is needed to be rendered in a format that is displayable in the front end application. For example, you can not view the Word document in your web application in its original format. However, you can do it by rendering the document pages as HTML pages or images.

The search feature is not the part of back-end GroupDocs.Viewer API. However, this feature is implementable in the front end application and currently it is available in GroupDocs.Viewer-for-.NET-WebForms-App for HTML based rendering.

In order to evaluate all the features of the API, please download the Examples project that contains the source code examples of all the features of the API. To learn more about the API, please visit the documentation.

Thanks Usman for the quick response, I tried the webforms solution sample and works for docx. As soon as i changed for pdf its started giving few errors. Though its generating the thumbnails and html but not able to render. I have updated the dll to the latest form nuget also. Am i missing something. Please advice. Following is the error screenshot.

image.png (19.0 KB)


Thanks for your response. We tested to render the PDF documents in GroupDocs.Viewer-for-.NET-WebForms-App but unable to reproduce your reported issue. Would you please check if you are getting this issue for specific PDF documents. In that case, please share with us the problematic document.

Hi Usman,

I have been trying with the solution you have provided in the link. I am also attaching the pdf. Earlier i was using the solution in .net based forms. It seems your solution is in MVC and has better UI. Is there any limitation with file size/no of pages in pdf etc for the same with unlicensed version.?

I have downloaded the temp license and now able to view pdf. But rotation works when its image format and search only works in html. I will check if any other questions are there before we decide to buy. Thanks Usman for all the help !


Thanks for sharing your concerns with us.

Yes, our open source document viewer applications include the ASP.NET MVC application as well as webforms application (listed below).

Yes, with the unlicensed version of GroupDocs.Viewer you will be able to render only first two pages of the document. For more details on evaluation limitations, please visit here.

GroupDocs.Viewer also allows you to rotate pages in HTML based rendering. However, currently, rotate page feature is available in image-based rendering in our open source applications. We have logged it in our GitHub issues as: for the implementation of this feature in our open source applications. We’ll keep you informed in case of any updates. The search feature is also available only for the HTML based rendering. However, we’ll check if we can provide it for image-based rendering as well.