Extending the header style in OpenXmlStyleOptions

src/MiniExcel.Core/Enums/CellAlignment.cs

@@ -0,0 +1,15 @@
+namespace MiniExcelLib.Core.Enums;
+
+public enum HorizontalCellAlignment
+{
+    Left,
+    Center,
+    Right
+}
+
+public enum VerticalCellAlignment
+{
+    Top,
+    Center,
+    Bottom
+}

src/MiniExcel.Core/OpenXml/Styles/Builder/DefaultSheetStyleBuilder.cs

@@ -1,4 +1,7 @@
-namespace MiniExcelLib.Core.OpenXml.Styles.Builder;
+using System.Drawing;
+using MiniExcelLib.Core.Enums;
+
+namespace MiniExcelLib.Core.OpenXml.Styles.Builder;
 
 internal partial class DefaultSheetStyleBuilder(SheetStyleBuildContext context, OpenXmlStyleOptions styleOptions)
     : SheetStyleBuilderBase(context)
@@ -13,6 +16,10 @@ internal partial class DefaultSheetStyleBuilder(SheetStyleBuildContext context,
         CellXfCount = 5
     };
 
+    private static readonly Color DefaultBackgroundColor = Color.FromArgb(0x284472C4);
+    private const HorizontalCellAlignment DefaultHorizontalAlignment = HorizontalCellAlignment.Left;
+    private const VerticalCellAlignment DefaultVerticalAlignment = VerticalCellAlignment.Bottom;
+
     private readonly SheetStyleBuildContext _context = context;
     private readonly OpenXmlStyleOptions _styleOptions = styleOptions;
 
@@ -134,7 +141,11 @@ protected override async Task GenerateFillAsync()
         await _context.NewXmlWriter.WriteStartElementAsync(_context.OldXmlReader.Prefix, "patternFill", _context.OldXmlReader.NamespaceURI).ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "patternType", null, "solid").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteStartElementAsync(_context.OldXmlReader.Prefix, "fgColor", _context.OldXmlReader.NamespaceURI).ConfigureAwait(false);
-        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "rgb", null, "284472C4").ConfigureAwait(false);
+
+        var bgColor = _styleOptions.HeaderStyle?.BackgroundColor ?? DefaultBackgroundColor;
+        var hexBgColor = $"{bgColor.A:X2}{bgColor.R:X2}{bgColor.G:X2}{bgColor.B:X2}";
+        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "rgb", null, hexBgColor).ConfigureAwait(false);
+
         await _context.NewXmlWriter.WriteEndElementAsync().ConfigureAwait(false);
         await _context.NewXmlWriter.WriteEndElementAsync().ConfigureAwait(false);
         await _context.NewXmlWriter.WriteEndElementAsync().ConfigureAwait(false);
@@ -346,10 +357,20 @@ protected override async Task GenerateCellXfAsync()
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "applyAlignment", null, "1").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "applyProtection", null, "1").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteStartElementAsync(_context.OldXmlReader.Prefix, "alignment", _context.OldXmlReader.NamespaceURI).ConfigureAwait(false);
-        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "horizontal", null, "left").ConfigureAwait(false);
-        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "vertical", null, "bottom").ConfigureAwait(false);
+
+        var horizontalAlignment = _styleOptions.HeaderStyle?.HorizontalAlignment ?? DefaultHorizontalAlignment;
+        var horizontalAlignmentStr = horizontalAlignment.ToString().ToLowerInvariant();
+        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "horizontal", null, horizontalAlignmentStr).ConfigureAwait(false);
+
+        var verticalAlignment = _styleOptions.HeaderStyle?.VerticalAlignment ?? DefaultVerticalAlignment;
+        var verticalAlignmentStr = verticalAlignment.ToString().ToLowerInvariant();
+        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "vertical", null, verticalAlignmentStr).ConfigureAwait(false);
+
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "textRotation", null, "0").ConfigureAwait(false);
-        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "wrapText", null, "0").ConfigureAwait(false);
+
+        var wrapHeader = (_styleOptions.HeaderStyle?.WrapText ?? false) ? "1" : "0";
+        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "wrapText", null, wrapHeader).ConfigureAwait(false);
+
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "indent", null, "0").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "relativeIndent", null, "0").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "justifyLastLine", null, "0").ConfigureAwait(false);
@@ -383,7 +404,10 @@ protected override async Task GenerateCellXfAsync()
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "horizontal", null, "general").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "vertical", null, "bottom").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "textRotation", null, "0").ConfigureAwait(false);
-        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "wrapText", null, _styleOptions.WrapCellContents ? "1" : "0").ConfigureAwait(false);
+
+        var wrapContent = _styleOptions.WrapCellContents ? "1" : "0";
+        await _context.NewXmlWriter.WriteAttributeStringAsync(null, "wrapText", null, wrapContent).ConfigureAwait(false);
+
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "indent", null, "0").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "relativeIndent", null, "0").ConfigureAwait(false);
         await _context.NewXmlWriter.WriteAttributeStringAsync(null, "justifyLastLine", null, "0").ConfigureAwait(false);

src/MiniExcel.Core/OpenXml/Styles/OpenXmlHeaderStyle.cs

@@ -0,0 +1,27 @@
+using System.Drawing;
+using MiniExcelLib.Core.Enums;
+
+namespace MiniExcelLib.Core.OpenXml.Styles;
+
+public class OpenXmlHeaderStyle
+{
+    /// <summary>
+    /// Whether to wrap the content of the header
+    /// </summary>
+    public bool WrapText { get; set; }
+
+    /// <summary>
+    /// The RGB background color in the filtered state
+    /// </summary>
+    public Color BackgroundColor { get; set; } = Color.FromArgb(0x284472C4);
+
+    /// <summary>
+    /// Horizontal alignment
+    /// </summary>
+    public HorizontalCellAlignment HorizontalAlignment { get; set; } = HorizontalCellAlignment.Left;
+
+    /// <summary>
+    /// Vertical alignment
+    /// </summary>
+    public VerticalCellAlignment VerticalAlignment { get; set; } = VerticalCellAlignment.Bottom;
+}

src/MiniExcel.Core/OpenXml/Styles/OpenXmlStyleOptions.cs

@@ -3,4 +3,5 @@ namespace MiniExcelLib.Core.OpenXml.Styles;
 public class OpenXmlStyleOptions
 {
     public bool WrapCellContents { get; set; }
+    public OpenXmlHeaderStyle? HeaderStyle { get; set; } 
 }