Task(1050427)-Add UG documentation for custom font registry feature in XlsIO

Document-Processing/Excel/Conversions/Excel-to-Image/NET/Worksheet-to-Image-Conversion.md

@@ -6,7 +6,7 @@ control: XlsIO
 documentation: UG
 ---
 
-# Worksheet to Image Conversion in .NET Excel Library
+# Excel Worksheet to Image Conversion in .NET Excel Library
 
 ## Assemblies Required
 
@@ -166,6 +166,156 @@ N> 3. Worksheet to image conversion is supported from .NET Framework 2.0 and .NE
 * Shrink to fit
 * Complex conditional formatting
 
+## Register custom fonts
+
+The .NET Excel library allows TrueType (`.ttf`) and OpenType (`.otf`) font files to be registered as custom fonts. The registered fonts are used during Excel-to-Image conversion when the required fonts are not installed on the system.
+
+The following code example shows how to register custom fonts and use them during Excel-to-Image conversion.
+
+{% tabs %}  
+{% highlight c# tabtitle="C# [Cross-platform]" playgroundButtonLink="https://raw.githubusercontent.com/SyncfusionExamples/XlsIO-Examples/master/Worksheet%20to%20Image/Custom%20Font/.NET/Custom%20Font/Custom%20Font/Program.cs,180" %}
+// Create a collection to store the custom font streams
+List<Stream> fontStreams = new List<Stream>();
+
+// Retrieve all font files from the specified directory
+foreach (string file in Directory.GetFiles(Path.GetFullPath(@"Data/MyFonts")))
+{
+    string extension = Path.GetExtension(file);
+
+    // Load only TrueType and OpenType font files
+    if (extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) ||
+        extension.Equals(".otf", StringComparison.OrdinalIgnoreCase))
+    {
+        // Read the font file and copy its content to a memory stream
+        FileStream fileStream = new FileStream(file, FileMode.OpenOrCreate, FileAccess.Read);
+        Stream stream = new MemoryStream();
+        fileStream.CopyTo(stream);
+        stream.Position = 0;
+        fontStreams.Add(stream);
+    }
+}
+
+// Register the custom fonts for use during Excel-to-Image conversion
+FontManager.RegisterFonts(fontStreams);
+
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+
+    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath(@"Data/Input.xlsx"));
+    IWorksheet sheet = workbook.Worksheets[0];
+
+    application.XlsIORenderer = new XlsIORenderer();
+
+    using (FileStream outputStream = new FileStream(Path.GetFullPath("Output/Image.png"), FileMode.Create, FileAccess.Write))
+    {
+        sheet.ConvertToImage(sheet.UsedRange, outputStream);
+    }
+}
+
+// Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(true);
+{% endhighlight %}
+
+{% highlight c# tabtitle="C# [Windows-specific]" %}
+// Create a collection to store the custom font streams
+List<Stream> fontStreams = new List<Stream>();
+
+// Retrieve all font files from the specified directory
+foreach (string file in Directory.GetFiles(Path.GetFullPath(@"Data/MyFonts")))
+{
+    string extension = Path.GetExtension(file);
+
+    // Load only TrueType and OpenType font files
+    if (extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) ||
+        extension.Equals(".otf", StringComparison.OrdinalIgnoreCase))
+    {
+        // Read the font file and copy its content to a memory stream
+        FileStream fileStream = new FileStream(file, FileMode.OpenOrCreate, FileAccess.Read);
+        Stream stream = new MemoryStream();
+        fileStream.CopyTo(stream);
+        stream.Position = 0;
+        fontStreams.Add(stream);
+    }
+}
+
+// Register the custom fonts for use during Excel-to-Image conversion
+FontManager.RegisterFonts(fontStreams);
+
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+
+    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath("Data/Input.xlsx"));
+
+    IWorksheet worksheet = workbook.Worksheets[0];
+
+    // Convert the specified Excel range to an image
+    Image image = worksheet.ConvertToImage(1, 1, 20, 7);
+
+    image.Save(Path.GetFullPath("Output/Sample.jpeg"),ImageFormat.Jpeg);
+
+    workbook.Close();
+}
+
+// Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(true);
+{% endhighlight %}
+
+{% highlight vb.net tabtitle="VB.NET [Windows-specific]" %}
+' Create a collection to store the custom font streams
+Dim fontStreams As New List(Of Stream)()
+
+' Retrieve all font files from the specified directory
+For Each file As String In Directory.GetFiles(Path.GetFullPath("Data/MyFonts"))
+
+    Dim extension As String = Path.GetExtension(file)
+
+    ' Load only TrueType and OpenType font files.
+    If extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) OrElse
+extension.Equals(".otf", StringComparison.OrdinalIgnoreCase) Then
+
+        ' Read the font file and copy its content to a memory stream
+        Dim fileStream As New FileStream(file, FileMode.OpenOrCreate, FileAccess.Read)
+
+        Dim stream As Stream = New MemoryStream()
+        fileStream.CopyTo(stream)
+        stream.Position = 0
+        fontStreams.Add(stream)
+
+        fileStream.Dispose()
+    End If
+Next
+
+' Register the custom fonts for use during Excel-to-image conversion
+FontManager.RegisterFonts(fontStreams)
+
+Using excelEngine As New ExcelEngine()
+    Dim application As IApplication = excelEngine.Excel
+    application.DefaultVersion = ExcelVersion.Xlsx
+
+    Dim workbook As IWorkbook = application.Workbooks.Open(Path.GetFullPath("Data/Input.xlsx"))
+
+    Dim worksheet As IWorksheet = workbook.Worksheets(0)
+
+    ' Convert the specified Excel range to an image
+    Dim image As Image = worksheet.ConvertToImage(1, 1, 20, 7)
+
+    ' Save the converted image in JPEG format
+    image.Save(Path.GetFullPath("Output/Sample.jpeg"), ImageFormat.Jpeg)
+
+    workbook.Close()
+End Using
+
+' Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(True)
+{% endhighlight %}
+{% endtabs %}
+
+A complete working example of registering custom fonts in C# is present on <a href="https://github.com/SyncfusionExamples/XlsIO-Examples/tree/master/Worksheet%20to%20Image/Custom%20Font/.NET/Custom%20Font" aria-label="GitHub example for registering custom fonts during worksheet-to-image conversion">this GitHub page</a>.
+
 ## See also
 
 * [Assemblies Information](https://help.syncfusion.com/document-processing/excel/excel-library/net/assemblies-required#converting-excel-worksheet-to-image) — manual assembly references.

Document-Processing/Excel/Conversions/Excel-to-Image/overview.md

@@ -171,6 +171,156 @@ N> 3. Worksheet to image conversion is supported from .NET Framework 2.0 and .NE
 * Shrink to fit
 * Complex conditional formatting
 
+## Register custom fonts
+
+The .NET Excel library allows TrueType (`.ttf`) and OpenType (`.otf`) font files to be registered as custom fonts. The registered fonts are used during Excel-to-Image conversion when the required fonts are not installed on the system.
+
+The following code example shows how to register custom fonts and use them during Excel-to-Image conversion.
+
+{% tabs %}  
+{% highlight c# tabtitle="C# [Cross-platform]" playgroundButtonLink="https://raw.githubusercontent.com/SyncfusionExamples/XlsIO-Examples/master/Worksheet%20to%20Image/Custom%20Font/.NET/Custom%20Font/Custom%20Font/Program.cs,180" %}
+// Create a collection to store the custom font streams
+List<Stream> fontStreams = new List<Stream>();
+
+// Retrieve all font files from the specified directory
+foreach (string file in Directory.GetFiles(Path.GetFullPath(@"Data/MyFonts")))
+{
+    string extension = Path.GetExtension(file);
+
+    // Load only TrueType and OpenType font files
+    if (extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) ||
+        extension.Equals(".otf", StringComparison.OrdinalIgnoreCase))
+    {
+        // Read the font file and copy its content to a memory stream
+        FileStream fileStream = new FileStream(file, FileMode.OpenOrCreate, FileAccess.Read);
+        Stream stream = new MemoryStream();
+        fileStream.CopyTo(stream);
+        stream.Position = 0;
+        fontStreams.Add(stream);
+    }
+}
+
+// Register the custom fonts for use during Excel-to-Image conversion
+FontManager.RegisterFonts(fontStreams);
+
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+
+    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath(@"Data/Input.xlsx"));
+    IWorksheet sheet = workbook.Worksheets[0];
+
+    application.XlsIORenderer = new XlsIORenderer();
+
+    using (FileStream outputStream = new FileStream(Path.GetFullPath("Output/Image.png"), FileMode.Create, FileAccess.Write))
+    {
+        sheet.ConvertToImage(sheet.UsedRange, outputStream);
+    }
+}
+
+// Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(true);
+{% endhighlight %}
+
+{% highlight c# tabtitle="C# [Windows-specific]" %}
+// Create a collection to store the custom font streams
+List<Stream> fontStreams = new List<Stream>();
+
+// Retrieve all font files from the specified directory
+foreach (string file in Directory.GetFiles(Path.GetFullPath(@"Data/MyFonts")))
+{
+    string extension = Path.GetExtension(file);
+
+    // Load only TrueType and OpenType font files
+    if (extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) ||
+        extension.Equals(".otf", StringComparison.OrdinalIgnoreCase))
+    {
+        // Read the font file and copy its content to a memory stream
+        FileStream fileStream = new FileStream(file, FileMode.OpenOrCreate, FileAccess.Read);
+        Stream stream = new MemoryStream();
+        fileStream.CopyTo(stream);
+        stream.Position = 0;
+        fontStreams.Add(stream);
+    }
+}
+
+// Register the custom fonts for use during Excel-to-Image conversion
+FontManager.RegisterFonts(fontStreams);
+
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+
+    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath("Data/Input.xlsx"));
+
+    IWorksheet worksheet = workbook.Worksheets[0];
+
+    // Convert the specified Excel range to an image
+    Image image = worksheet.ConvertToImage(1, 1, 20, 7);
+
+    image.Save(Path.GetFullPath("Output/Sample.jpeg"),ImageFormat.Jpeg);
+
+    workbook.Close();
+}
+
+// Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(true);
+{% endhighlight %}
+
+{% highlight vb.net tabtitle="VB.NET [Windows-specific]" %}
+' Create a collection to store the custom font streams
+Dim fontStreams As New List(Of Stream)()
+
+' Retrieve all font files from the specified directory
+For Each file As String In Directory.GetFiles(Path.GetFullPath("Data/MyFonts"))
+
+    Dim extension As String = Path.GetExtension(file)
+
+    ' Load only TrueType and OpenType font files.
+    If extension.Equals(".ttf", StringComparison.OrdinalIgnoreCase) OrElse
+extension.Equals(".otf", StringComparison.OrdinalIgnoreCase) Then
+
+        ' Read the font file and copy its content to a memory stream
+        Dim fileStream As New FileStream(file, FileMode.OpenOrCreate, FileAccess.Read)
+
+        Dim stream As Stream = New MemoryStream()
+        fileStream.CopyTo(stream)
+        stream.Position = 0
+        fontStreams.Add(stream)
+
+        fileStream.Dispose()
+    End If
+Next
+
+' Register the custom fonts for use during Excel-to-image conversion
+FontManager.RegisterFonts(fontStreams)
+
+Using excelEngine As New ExcelEngine()
+    Dim application As IApplication = excelEngine.Excel
+    application.DefaultVersion = ExcelVersion.Xlsx
+
+    Dim workbook As IWorkbook = application.Workbooks.Open(Path.GetFullPath("Data/Input.xlsx"))
+
+    Dim worksheet As IWorksheet = workbook.Worksheets(0)
+
+    ' Convert the specified Excel range to an image
+    Dim image As Image = worksheet.ConvertToImage(1, 1, 20, 7)
+
+    ' Save the converted image in JPEG format
+    image.Save(Path.GetFullPath("Output/Sample.jpeg"), ImageFormat.Jpeg)
+
+    workbook.Close()
+End Using
+
+' Clear the registered fonts and dispose their associated streams
+FontManager.ClearRegisteredFonts(True)
+{% endhighlight %}
+{% endtabs %}
+
+A complete working example of registering custom fonts in C# is present on <a href="https://github.com/SyncfusionExamples/XlsIO-Examples/tree/master/Worksheet%20to%20Image/Custom%20Font/.NET/Custom%20Font" aria-label="GitHub example for registering custom fonts during worksheet-to-image conversion">this GitHub page</a>.
+
 ## See also
 
 * [Worksheet to Image conversion in .NET](https://help.syncfusion.com/document-processing/excel/conversions/excel-to-image/net/worksheet-to-image-conversion) — runnable code samples for each platform.