Merge pull request #10 from fahadadeel/main

Add worksheet tab color functionality

Author: fahadadeel

Excel/WorksheetColorExtensions.cs

@@ -0,0 +1,202 @@
+using System;
+using DocumentFormat.OpenXml;
+using DocumentFormat.OpenXml.Spreadsheet;
+
+namespace Openize.Cells
+{
+    /// <summary>
+    /// Provides extension methods for managing worksheet tab colors in Excel workbooks.
+    /// </summary>
+    public static class WorksheetColorExtensions
+    {
+        /// <summary>
+        /// Sets the tab color for a worksheet using RGB values.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to set the tab color for.</param>
+        /// <param name="red">The red component (0-255).</param>
+        /// <param name="green">The green component (0-255).</param>
+        /// <param name="blue">The blue component (0-255).</param>
+        /// <exception cref="ArgumentNullException">Thrown when worksheet is null.</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when color components are outside the valid range.</exception>
+        public static void SetTabColor(this Worksheet worksheet, byte red, byte green, byte blue)
+        {
+            if (worksheet == null)
+                throw new ArgumentNullException(nameof(worksheet));
+
+            string hexColor = $"{red:X2}{green:X2}{blue:X2}";
+            SetTabColorByHex(worksheet, hexColor);
+        }
+
+        /// <summary>
+        /// Sets the tab color for a worksheet using an HTML-style hex color code.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to set the tab color for.</param>
+        /// <param name="hexColor">The hex color code (e.g., "FF0000" for red).</param>
+        /// <exception cref="ArgumentNullException">Thrown when worksheet is null.</exception>
+        /// <exception cref="ArgumentException">Thrown when hexColor is null, empty, or invalid.</exception>
+        public static void SetTabColorByHex(this Worksheet worksheet, string hexColor)
+        {
+            if (worksheet == null)
+                throw new ArgumentNullException(nameof(worksheet));
+
+            if (string.IsNullOrEmpty(hexColor))
+                throw new ArgumentException("Hex color cannot be null or empty.", nameof(hexColor));
+
+            // Strip # if present
+            if (hexColor.StartsWith("#"))
+                hexColor = hexColor.Substring(1);
+
+            // Validate hex color format
+            if (!IsValidHexColor(hexColor))
+                throw new ArgumentException("Invalid hex color format. Expected format: RRGGBB", nameof(hexColor));
+
+            // Get access to the internal OpenXML worksheet
+            var openXmlWorksheetPart = GetOpenXmlWorksheetPart(worksheet);
+            if (openXmlWorksheetPart == null)
+                return;
+
+            var openXmlWorksheet = openXmlWorksheetPart.Worksheet;
+
+            // Get or create the SheetProperties element
+            SheetProperties sheetProperties = openXmlWorksheet.GetFirstChild<SheetProperties>();
+            if (sheetProperties == null)
+            {
+                sheetProperties = new SheetProperties();
+                openXmlWorksheet.InsertAt(sheetProperties, 0);
+            }
+
+            // Get or create the TabColor element
+            TabColor tabColor = sheetProperties.GetFirstChild<TabColor>();
+            if (tabColor == null)
+            {
+                tabColor = new TabColor();
+                sheetProperties.AppendChild(tabColor);
+            }
+
+            // Set the RGB value
+            tabColor.Rgb = hexColor;
+
+            // Save the changes
+            openXmlWorksheet.Save();
+        }
+
+        /// <summary>
+        /// Gets the tab color of a worksheet as RGB values.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to get the tab color from.</param>
+        /// <param name="red">Output parameter to receive the red component.</param>
+        /// <param name="green">Output parameter to receive the green component.</param>
+        /// <param name="blue">Output parameter to receive the blue component.</param>
+        /// <returns>True if a tab color is set; otherwise, false.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when worksheet is null.</exception>
+        public static bool GetTabColor(this Worksheet worksheet, out byte red, out byte green, out byte blue)
+        {
+            red = 0;
+            green = 0;
+            blue = 0;
+
+            if (worksheet == null)
+                throw new ArgumentNullException(nameof(worksheet));
+
+            string hexColor = GetTabColorAsHex(worksheet);
+            if (string.IsNullOrEmpty(hexColor))
+                return false;
+
+            // Parse the hex color
+            red = Convert.ToByte(hexColor.Substring(0, 2), 16);
+            green = Convert.ToByte(hexColor.Substring(2, 2), 16);
+            blue = Convert.ToByte(hexColor.Substring(4, 2), 16);
+
+            return true;
+        }
+
+        /// <summary>
+        /// Gets the tab color of a worksheet as a hex color code.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to get the tab color from.</param>
+        /// <returns>The tab color as a hex color code, or null if no tab color is set.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when worksheet is null.</exception>
+        public static string GetTabColorAsHex(this Worksheet worksheet)
+        {
+            if (worksheet == null)
+                throw new ArgumentNullException(nameof(worksheet));
+
+            // Get access to the internal OpenXML worksheet
+            var openXmlWorksheetPart = GetOpenXmlWorksheetPart(worksheet);
+            if (openXmlWorksheetPart == null)
+                return null;
+
+            var openXmlWorksheet = openXmlWorksheetPart.Worksheet;
+
+            // Check if tab color is set
+            SheetProperties sheetProperties = openXmlWorksheet.GetFirstChild<SheetProperties>();
+            if (sheetProperties == null)
+                return null;
+
+            TabColor tabColor = sheetProperties.GetFirstChild<TabColor>();
+            if (tabColor == null || string.IsNullOrEmpty(tabColor.Rgb))
+                return null;
+
+            return tabColor.Rgb;
+        }
+
+        /// <summary>
+        /// Removes the tab color from a worksheet.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to remove the tab color from.</param>
+        /// <exception cref="ArgumentNullException">Thrown when worksheet is null.</exception>
+        public static void RemoveTabColor(this Worksheet worksheet)
+        {
+            if (worksheet == null)
+                throw new ArgumentNullException(nameof(worksheet));
+
+            // Get access to the internal OpenXML worksheet
+            var openXmlWorksheetPart = GetOpenXmlWorksheetPart(worksheet);
+            if (openXmlWorksheetPart == null)
+                return;
+
+            var openXmlWorksheet = openXmlWorksheetPart.Worksheet;
+
+            // Check if tab color is set
+            SheetProperties sheetProperties = openXmlWorksheet.GetFirstChild<SheetProperties>();
+            if (sheetProperties == null)
+                return;
+
+            TabColor tabColor = sheetProperties.GetFirstChild<TabColor>();
+            if (tabColor != null)
+            {
+                tabColor.Remove();
+                openXmlWorksheet.Save();
+            }
+        }
+
+        /// <summary>
+        /// Validates a hex color code.
+        /// </summary>
+        /// <param name="hexColor">The hex color code to validate.</param>
+        /// <returns>True if the hex color code is valid; otherwise, false.</returns>
+        private static bool IsValidHexColor(string hexColor)
+        {
+            if (string.IsNullOrEmpty(hexColor))
+                return false;
+
+            // Standard hex color format is either RRGGBB or AARRGGBB
+            return System.Text.RegularExpressions.Regex.IsMatch(hexColor, "^[0-9A-Fa-f]{6}([0-9A-Fa-f]{2})?$");
+        }
+
+        /// <summary>
+        /// Gets the OpenXML worksheet part from a Worksheet object.
+        /// </summary>
+        /// <param name="worksheet">The worksheet to get the OpenXML part from.</param>
+        /// <returns>The OpenXML worksheet part, or null if not available.</returns>
+        private static DocumentFormat.OpenXml.Packaging.WorksheetPart GetOpenXmlWorksheetPart(Worksheet worksheet)
+        {
+            // Use reflection to access the _worksheetPart field from the Worksheet class
+            var fieldInfo = worksheet.GetType().GetField("_worksheetPart", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+            if (fieldInfo == null)
+                return null;
+
+            return fieldInfo.GetValue(worksheet) as DocumentFormat.OpenXml.Packaging.WorksheetPart;
+        }
+    }
+}