thanks for your help i have another problem the version i am using for groupdoc is very old its 2.7.0.0. How i can implement same problem with this version?
Thanks for coming back to us.
You are using a very old version of GroupDocs.Viewer which is now obsolete and not supported anymore. We recommend you to please migrate to the next generation GroupDocs.Viewer API. Please note that the next generation API (starting from v3.0.0) is completely different from the older versions and front-end UI has been disintegrated from the back-end API. Now, you will have to create your own front end application that will be used to display the HTML pages or images rendered by the back-end GroupDocs.Viewer API.
We recommend you to please have a look at the documentation of the next generation API. To explore and evaluate the features of the API please download the examples project.