Bug/s1035 (#2334)

* Initial fix

* Better solution using existing data-structures

Author: OssianEPPlus

src/EPPlus/Export/HtmlExport/Enums/ePictureInclude.cs

@@ -29,6 +29,10 @@ public enum ePictureInclude
         /// <summary>
         /// Include the images in the html export.
         /// </summary>
-        Include
+        Include,
+        /// <summary>
+        /// Include the images only in the HTML.
+        /// </summary>
+        IncludeInHtmlOnly
     }
 }

src/EPPlus/Export/HtmlExport/Exporters/Internal/HtmlExporterBaseInternal.cs

@@ -11,10 +11,12 @@ Date               Author                       Change
   6/4/2022         EPPlus Software AB           ExcelTable Html Export
  *************************************************************************************************/
 using OfficeOpenXml.Core;
+using OfficeOpenXml.Drawing;
 using OfficeOpenXml.Drawing.Interfaces;
 using OfficeOpenXml.Export.HtmlExport.Accessibility;
 using OfficeOpenXml.Export.HtmlExport.HtmlCollections;
 using OfficeOpenXml.Export.HtmlExport.Parsers;
+using OfficeOpenXml.Export.HtmlExport.Translators;
 using OfficeOpenXml.Table;
 using OfficeOpenXml.Utils;
 using OfficeOpenXml.Utils.String;
@@ -146,7 +148,7 @@ protected HTMLElement GetThead(ExcelRangeBase range, List<string> headers = null
 
                     AddTableData(table, contentElement, col);
 
-                    if (Settings.Pictures.Include == ePictureInclude.Include)
+                    if (Settings.Pictures.Include == (ePictureInclude.Include | ePictureInclude.IncludeInHtmlOnly))
                     {
                         image = GetImage(cell.Worksheet.PositionId, cell._fromRow, cell._fromCol);
                     }
@@ -267,7 +269,7 @@ protected HTMLElement GetTableBody(ExcelRangeBase range, int row, int endRow)
 
                     SetColRowSpan(range, tblData, cell);
 
-                    if (Settings.Pictures.Include == ePictureInclude.Include)
+                    if (Settings.Pictures.Include == (ePictureInclude.Include | ePictureInclude.IncludeInHtmlOnly))
                     { 
                         image = GetImage(cell.Worksheet.PositionId, cell._fromRow, cell._fromCol);
                     }
@@ -381,6 +383,24 @@ protected void AddContent(ExcelRangeBase cell, HTMLElement contentElement)
             }
         }
 
+
+        private object GetContentType(ePictureType type)
+        {
+            switch (type)
+            {
+                case ePictureType.Ico:
+                    return "image/vnd.microsoft.icon";
+                case ePictureType.Jpg:
+                    return "image/jpeg";
+                case ePictureType.Svg:
+                    return "image/svg+xml";
+                case ePictureType.Tif:
+                    return "image/tiff";
+                default:
+                    return $"image/{type}";
+            }
+        }
+
         protected void AddImage(HTMLElement parent, HtmlExportSettings settings, HtmlImage image, object value)
         {
             if (image != null)
@@ -393,7 +413,18 @@ protected void AddImage(HTMLElement parent, HtmlExportSettings settings, HtmlIma
                 {
                     child.AddAttribute("id", imageName);
                 }
-                child.AddAttribute("class", $"{settings.StyleClassPrefix}image-{name} {settings.StyleClassPrefix}image-prop-{imageName}");
+
+                if(settings.Pictures.Include == ePictureInclude.IncludeInHtmlOnly)
+                {
+                    ePictureType? type;
+                    var _encodedImage = ImageEncoder.EncodeImage(image, out type);
+
+                    child.AddAttribute("src", $"data:{GetContentType(type.Value)};base64,{_encodedImage}");
+                }
+                else
+                {
+                    child.AddAttribute("class", $"{settings.StyleClassPrefix}image-{name} {settings.StyleClassPrefix}image-prop-{imageName}");
+                }
                 parent._childElements.Add(child);
             }
         }

src/EPPlus/Export/HtmlExport/Settings/HtmlPictureSettings.cs

@@ -22,6 +22,7 @@ internal HtmlPictureSettings()
         {
 
         }
+
         /// <summary>
         /// If picture drawings should be included in the html. Default is <see cref="ePictureInclude.Exclude"/>
         /// </summary>

src/EPPlusTest/Export/HtmlExport/RangeExporterTests.cs

@@ -195,6 +195,27 @@ public async Task WriteImagesAsync()
                 Assert.AreEqual(html, htmlAsync);
             }
         }
+
+        [TestMethod]
+        public async Task WriteImagesAsyncHTMLOnlyEmbed()
+        {
+            using (var p = OpenTemplatePackage("20-CreateAFileSystemReport.xlsx"))
+            {
+                var sheet = p.Workbook.Worksheets[0];
+                var exporter = sheet.Cells["A1:E30"].CreateHtmlExporter();
+
+                exporter.Settings.SetColumnWidth = true;
+                exporter.Settings.SetRowHeight = true;
+                exporter.Settings.Pictures.Include = ePictureInclude.IncludeInHtmlOnly;
+                exporter.Settings.Minify = false;
+                exporter.Settings.Encoding = Encoding.UTF8;
+
+                var html = exporter.GetHtmlString();
+                var htmlAsync = await exporter.GetSinglePageAsync();
+                File.WriteAllText("c:\\temp\\" + sheet.Name + "_htmlOnly.html", html);
+            }
+        }
+
         [TestMethod]
         public void ExportMultipleRanges()
         {