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Document conversion API usage in .NET


Thank you for giving a try to the new GroupDocs.Conversion

Here are the answers to your each question

  1. Excel:
  • Please share more details about “Show Grid”
  • Yes it supports multiple worksheets
  1. PowerPoint presentation:
  • Sorry this version does not allow handling comments but by default comments are skipped while conversion.
  • Yes you can specify number of slides to convert by using SlidesSaveOption

new SlidesSaveOptions { OutputType = OutputType.String, NumPagesToConvert = 2, PageNumber = 2 }

    • Yes you can specify the image quality by setting image DPI property of ImageSaveOptions

    new ImageSaveOptions { ConvertFileType = ImageFileType.Jpg, OutputType = OutputType.String, Dpi = 1600 }

    1. PDF:
    • Yes you can navigate page by page to convert by using PdfSaveOption

    new PdfSaveOptions { OutputType = OutputType.String, NumPagesToConvert = 2, PageNumber = 2 }

    If you will need any help or you will have any other questions please feel free to ask.

    Warm Regards

    The issues you have found earlier (filed as CONVERSIONNET-710;CONVERSIONNET-734;CONVERSIONNET-750;CONVERSIONNET-782 ) have been fixed in this update.

    This message was posted using Notification2Forum from Downloads module by groupdocs.notifier.


    Thanks for your response.
    Sorry i forget to tell that i’m using groupdocs to convert office documents and pdf to HTML.
    1. Excel
    • Show Grid means, if i don’t have borders - html will not show cells borders.
    • Ok i see it showing multiple worksheets (earlier the other worksheets was empty, that’s why i didn’t saw).
  1. PowerPoint:
    • Ok got it
    • The question is it possible to have pagination on html page? Now all the converted documents have no pagination, it have just scrolling down concept. We want something similar to Office 365 (sharepoint) powerpoint online viewer.
    • I’m using HtmlSaveOptions - not possible to use what you suggest, i think
  2. Pdf:
    • Same thing as with powerpoint pagination.

    As I said, my manager wants similar to office 365 document viewer. And there another question about file preview? Can it be achieved by reduce font-size and show in popup or may be some another way?


    Thank you for the details.

    Converting office documents to HTML format allow these HTML Options in this release.

    HtmlSaveOptions htmlSaveOptions = new HtmlSaveOptions();







    1. Excel:

    a. Yes it renders same formatting as original file, if original file have borders then it only display borders for those cells.

    2. PowerPoint:

    a. It converts all slides in a same single file; however you can specify number of slides to convert. For example you can convert one slide and render as HTML and on your custom pagination event you can convert other slide and render as HTML and so on.

    3. Pdf:

    a. Same applies as PowerPoint pagination.

    We suggest you to please look for our great product GroupDocs.Viewer that will cover your requirements.

    If you will need any help or you will have any other questions please feel free to ask.

    Warm Regards


    thanks for your response.

    My requirments are next: we have web service and mvc web app. Web service have access to file and provide file stream to web app. And html conversion have to be done at web service side, because no one should have access to the original file. So can you advice is GroupDocs.Viewer able to cover this?

    Thank you for sharing your requirements.

    Yes GroupDocs.Viewer for .NET 3.0.0 can handle your requirements.

    Please find below some resources to quickly get started with GroupDocs.Viewer:

    GroupDocs.Viewer Downloads:
    GroupDocs.Viewer Docs:
    GroupDocs.Viewer Examples:
    GroupDocs.Viewer Videos:

    In case, you have problems using the GroupDocs.Viewer, please create a new thread on this forum. So we can keep track of your problems. Thanks for your understanding and cooperation.

    With Best Regards


    I’m back to use GroupDocs.Conversion and code my own js pagination.

    But we still have questions:
    1. Excel - is it possible to keep showing cells borders (not user borders, but excel cells borders itself)? May be possible add some custom style to add borders?
    2. Word document have page framing (it’s separating with borders) but others files do not have this? is it possible to turn on? I know I can add my own style, just asking if your library can do it without my effort.
    3. Looks like Conversion library have no Watermark support unlike Viewer, am i right?
    4. We found some presentation problem in powerpoint for table. Please refer to attachments.


    Thank you for giving a try to the new GroupDocs.Conversion API

    Here are the answers to your each question

    1. Excel - GroupDocs.Conversion export documents with all original formatting and contents, while converting documents you cannot edit contents.
    2. Word Document - Original page framing (Page Border) will convert automatically, for custom styling you can convert page by page and can display in specific framing format.
    3. Watermarks – Currently it’s not supported but we will consider this in future releases.
    4. Presentation – We have converted Excel file to PowerPoint and it display table properly

    Can you please provide more details about your conversion scenario and share your sample input file so we can identify and resolve issue?

    If you will need any help or you will have any other questions please feel free to ask.

    Warm Regards


    Thanks you for your answers

    1. Ok, but is it possible for me to add some css to turn on borders for all cells?
    2. I’m asking about PDF document - there no page border?
    3. Ok
    4. See attachment (attached zip archive)

    Hello ,

    Thank you for the providing details, Please see our answer
    for each points.

    1. Currently it is not possible to add CSS using
      GroupDocs.Conversion API but you can achieve that by converting document to
      HTML format and add inline style for table border and you can keep the html
      format or can convert html to any other document format.
    2. You can convert PDF document page by page to HTML and add
      border style for each page and use that HTML to convert in any other document format.
    3. Ok
    4. We have tested Conversion scenario
      with your provided presentation document and we found issues in conversion. We have
      logged this issue. When we will have any update about this issue, we will notify you.We apologize for the inconvenience.

    If you will need any help or you will have any other
    questions please feel free to ask.

    Warm Regards

    <!–[if gte mso 9]>
    <m:mathFont m:val=“Cambria Math”/>
    <m:brkBin m:val=“before”/>
    <m:brkBinSub m:val="–"/>
    <m:smallFrac m:val=“off”/>
    <m:lMargin m:val=“0”/>
    <m:rMargin m:val=“0”/>
    <m:defJc m:val=“centerGroup”/>
    <m:wrapIndent m:val=“1440”/>
    <m:intLim m:val=“subSup”/>
    <m:naryLim m:val=“undOvr”/>
    <![endif]–><!–[if gte mso 10]>

    /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}



    Thanks for your help, I’m appreciate it.

    You told me that it possible to add inline style for converted excel document. But there is no ‘table’, it convert with using ‘div’, and if i add border to these divs - it will not looks like excel cells. Am i doing something wrong?

    I also have some technical questions, if you can help:
    1. I have some pdf document, and when I call ConversionHandler.Convert(str, FileName, options) it hang and never respond. I know it does not depend on file itself, but depends on the stream (i have different different storage types, like azure, aws). So, do you know under what condition this method can hang? May be i can turn on some logging?

    2. I’m now displaying converted HTML in bootstrap modal. The problem I faced that for Excel and PDF documents - the images (background and others) moving out of their correct place. I found that it can be fixed for my case by set css ‘zoom: 0.875;’ to div with class ‘stl_03’. After i set - all looks fine. I have attached screen shot with problem. Do you have exp of such issue? May be you have any idea what can cause this?

    I know both problem are very specific problems, i’m just asking on possible reasons of my issues.


    Thank you for appreciating and sharing details.

    Yes it is true converted HTML render table as DIV tags and classes for each DIV, I am afraid you need to apply custom style for DIV.

    1. We have tested this (Stream to use with Azure, AWS) scenario using a some big size PDF file like 3 MB of file to convert in to HTML and result as in Stream and it works perfectly.
    • You can try to first convert file to HTML and read in stream and output path to local system/server and then use stream object OR read file from path and save to Azue,AWS.
    2. We have also tested this scenario and rendered HTML file display same formatting as original file But when we use converted HTML with custom CSS in page like Bootstrap effect the formatting by overwriting CSS classes.
    • You will required to handle your custom theme/Bootstrap classes to use converted HTML.

    If you will need any help or you will have any other questions please feel free to ask.

    Warm Regards


    For excel and custom style for div it’s not true as it’s not possible. It will not looks like a cells

    Ok, your answers was not really helpful, but thanks anyway.

    Another qn about excel. Since it support multiple sheets - is there i can extract Sheet name and use as label in the beginning of the next sheet? is there an indication that there another sheet starts?


    Sorry for the inconvenience, We are trying our best to make our next generation API’s to do jobs easily and high performance although all scenarios cannot be cover .

    To convert Excel file to HTML/Images you can convert page by page / Sheet by Sheet, please have a look at sample code using HtmlSaveOptions

    var saveOptions = new HtmlSaveOptions


    PageNumber = 2,

    NumPagesToConvert = 1,

    OutputType = OutputType.String


    var convertedDocumentPath = conversionHandler.Convert<string>(“E:/SampleExcel.xlsx”, saveOptions);

    Note: There is a limitation in evaluation version for all pages conversion (try to use first three sheets to test scenario).

    We have new release of GroupDocs.Conversion API for .NET scheduled soon with more options/features and fixes; please wait till that as that will cover more scenarios.

    If you will need any help or you will have any other questions please feel free to ask.

    Warm Regards


    Sorry, but you are not answering on the question.
    I’ve asked is it possible to differentiate different sheets? from your codes you are converting page by page, but not sheet by sheet. As I see now, it’s not possible. and there no sheet name I can find.

    Do you have scheduled date for new release? Is there release notes for your upcoming release?

    While testing today, I can see that excel is weak side of GroupDocs.Conversion. Hope new release will fix the issues

    Document 1. somehow the last page (there 3 sheets by 1 page in each) have different css class. all have stl_02, but last one - stl_10. So when i tried to add page borders - last page have different size, but without borders it cannot be observed.

    Document 2. This is complex document. Multiple sheets (9), different tables. So it does not return me all the pages. Cannot provide you this doc, i will try create similar excel and replicate with it.


    Sorry for the inconvenience. we have tested the Page by Page scenario for HTML output as well Images output, however the for rendering images working as each sheet converts to an Image file but for HTML rendering by using Paging there are issues and it does not convert each sheet as a separate page.

    PageNumber property in actual is a SheetNumber it is working for Image rendering but not for HTML rendering.

    We have reported this issue to Product team once we have any update from them we will inform you here.

    New release 3.1.0 of GroupDocs.Conversion for .NET is now available with CallBack and FileType features with more improvements; however these new logs are not covered in this release and will be consider for fix and improvements.

    Thanks you for your patience.


    Warm Regards<o:p></o:p>


    Thanks for sharing link for new release, i’ve downloaded.

    I’ve attached document, that i talked about in my previous post. Can you help me verify whether you see the issue in conversion of this excel or not. And is this the same issue as in your last post or it’s new. Thanks

    I have fixed by myself issue with document 1, just force to use css class ‘stl_02’ for pages for excel converted html. But this one (document 2 issue) i cannot fix.

    I’ve also added style for page numbers for PDF and WORD documents. I think it’s useful and will be good that your library can do it as an option.


    Thank you for the details.

    We have verified the documents on new 3.1.0 release and found issues and notified Product team for solution.

    Product team is already notified for these points

    • Default Border Handling
    • Excel Sheet Level Handling
    • PPTX/PPT Conversion Issues

    Thank you for your patience.

    Warm Regards


    Ok I got it.

    Found one more issue. See attached screen shot. At the left side you can see letters overlapped in ‘AVD’ and ‘Now’ words. And i found strange ‘font-family’. Every time it generate something new: LILPHA+LiberationSerif.
    Can you comment?


    Thank you for the details,

    We are notifying this to Product Team to look in to it for Andriod or other specifics for solution.

    Thank you for your patience.

    Warm Regards,