Use Office File API on Linux

• Dec 06, 2023
• 4 minutes to read

This tutorial describes how to create a simple Office File API application for .NET on Linux.

Prerequisites

Add Common Libraries

• The .NET library of the required version.

• The font libraries below (based on your Linux distribution) to measure, render, and export document text to PDF within your Office File API application.

  Ubuntu

  sudo apt-get install -y libc6 libicu-dev libfontconfig1
  

  Debian

  sudo apt-get install -y libc6 libicu-dev libfontconfig1
  

  CentOS / RHEL / Fedora

  sudo yum install -y glibc-devel libicu fontconfig
  

  openSUSE

  sudo zypper install -y libicu fontconfig
  

  Alpine

  sudo apk add icu-libs icu-data-full fontconfig
  

• Packaged fonts. To install font files on your machine, put them in the /usr/share/fonts folder and execute the ‘fc-cache’ command to update fontconfig cache files.

  You can also install the ttf-mscorefonts-installer package to add Microsoft TrueType core fonts (Arial, Times New Roman, Courier New, and so on) to your system. Run one of the following terminal commands to install this package and accept the license agreement.

  Ubuntu

  sudo apt-get install ttf-mscorefonts-installer
  

  Debian

  sudo apt install ttf-mscorefonts-installer -y
  

  CentOS / RHEL / Fedora

  sudo rpm -i https://downloads.sourceforge.net/project/mscorefonts2/rpms/msttcore-fonts-installer-2.6-1.noarch.rpm
  

  openSUSE

  sudo zypper install -y ttf-mscorefonts-installer
  

  Alpine

  apk --no-cache add msttcorefonts-installer
  

• If your application needs to render JPEG images within PDF files, install the packages below based on your Linux distribution (or any other packages that implement libjpeg API v6.2 or v8.0):

  Ubuntu

  sudo apt install -y libjpeg-turbo8
  

  Debian

  sudo apt install -y libjpeg62-turbo
  

  CentOS / RHEL / Fedora

  sudo yum install -y libjpeg-turbo
  

  openSUSE

  sudo zypper install -y libjpeg8
  

  Alpine

  apk add libjpeg-turbo
  

Add Drawing Engine Libraries

Add libraries related to the drawing engine to your application. The Office File API can use the following two drawing engines. Note that each engine is compatible with a certain range of System.Drawing.Common library versions.

Drawing Engine	System.Drawing.Common version
libgdiplus-based Drawing Engine	6 and earlier
SkiaSharp-based Drawing Library	All versions

How Office File API Chooses an Engine

The Office File API looks for drawing library references and enables the corresponding engine. The choice is also restricted by System.Drawing.Common library compatibility, as outlined in the table above. If the application contains references for both engines (that is, libgdiplus and DevExpress.Drawing.Skia), the libgdiplus-based engine is used. If no references are available, an exception is thrown.

Refer to the following article for more information on the drawing engines: DevExpress.Drawing Graphics Library

Libgdiplus-Based Drawing Engine

In addition to the libraries listed above, the libgdiplus-based drawing engine requires the following packages:

• libgdiplus
• harfbuzz
• freetype

Add the Mono repository to your system to install the latest libgdiplus version or use the corresponding terminal commands (depending on your Linux distribution).

SkiaSharp-Based Drawing Engine

Make sure that you add the DevExpress.Drawing.Skia package to your application to use the SkiaSharp-Based drawing engine.

If you use the the System.Drawing.Common package v7 and later, the Skia-based engine is enabled automatically and the libgdiplus library is not required.

Create an Application

Create a folder for you project (OfficeConsoleApp in this example) and open this folder in Visual Studio Code.

Click View → Terminal in the main menu to open the integrated terminal. Use the dotnet new command to create a new console application.

Create a C# project

dotnet new console

Create a VB project

dotnet new console -lang VB

This command adds the following files to your folder:

• OfficeConsoleApp.csproj / OfficeConsoleApp.vbproj

• Program.cs / Program.vb.

Add DevExpress.Document.Processor Package

Obtain your NuGet Feed URL and install the DevExpress.Document.Processor NuGet package as described in the following topic: Use NuGet Packages to Install Office File API Components.

Add the DevExpress.Pdf.SkiaRenderer package to enable rendering of PDF page content within your app.

Important

You need a license for the DevExpress Office File API Subscription or DevExpress Universal Subscription to use this package in production code.

Insert Code

Paste the code below in the Main method of the Program.cs file (or the Program.vb file’s Main procedure for Visual Basic). The following example converts a DOCX file to PDF:

C#

using DevExpress.XtraRichEdit;
// ...

static void Main(string[] args) {
    using (var wordProcessor =
        new RichEditDocumentServer()) {
        // Load a document from a file.
        wordProcessor.LoadDocument("Document.docx", DocumentFormat.OpenXml);
        // Export the document to PDF.
        wordProcessor.ExportToPdf("PdfDocument.pdf");
    }
}

VB.NET

Imports DevExpress.XtraRichEdit
' ...

Sub Main(args As String())
    Using wordProcessor As RichEditDocumentServer = New RichEditDocumentServer()
        ' Load a document from a file.
        wordProcessor.LoadDocument("Document.docx", DocumentFormat.OpenXml)
        ' Export the document to PDF.
        wordProcessor.ExportToPdf("PdfDocument.pdf")
    End Using
End Sub

Run the Application

Type dotnet run in the terminal window to run the program.

dotnet run

The following image illustrates the result. This tutorial uses Visual Studio Code.