added files

Author: rachitdhar

.gitignore

@@ -0,0 +1,100 @@
+using OfficeOpenXml;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+
+namespace massive_sheet_splitter
+{
+    public class ExcelSheetData
+    {
+        public string SheetName { get; set; }
+        public List<List<string>> Rows { get; set; } = new List<List<string>>();
+    }
+
+    public class ExcelHelper
+    {
+        public ExcelHelper()
+        {
+            ExcelPackage.License.SetNonCommercialPersonal("rcht");
+        }
+
+        public List<ExcelSheetData> read_excel(string file_path)
+        {
+            var workbookData = new List<ExcelSheetData>();
+
+            using (var package = new ExcelPackage(new FileInfo(file_path)))
+            {
+                foreach (var sheet in package.Workbook.Worksheets)
+                {
+                    var sheetData = new ExcelSheetData { SheetName = sheet.Name };
+
+                    int rowCount = sheet.Dimension.Rows;
+                    int colCount = sheet.Dimension.Columns;
+
+                    for (int row = 1; row <= rowCount; row++)
+                    {
+                        var rowData = new List<string>();
+                        for (int col = 1; col <= colCount; col++)
+                        {
+                            rowData.Add(sheet.Cells[row, col].Text);
+                        }
+                        sheetData.Rows.Add(rowData);
+                    }
+
+                    workbookData.Add(sheetData);
+                }
+            }
+
+            return workbookData;
+        }
+
+        public void write_excel(string dest_path, List<ExcelSheetData> sheets, int start_row, int end_row, int last_header_row)
+        {
+            using (var package = new ExcelPackage())
+            {
+                foreach (var sheetData in sheets)
+                {
+                    var ws = package.Workbook.Worksheets.Add(sheetData.SheetName);
+
+                    int currentRow = 1;
+                    for (int i = 0; i < last_header_row; i++)
+                    {
+                        for (int col = 0; col < sheetData.Rows[i].Count; col++)
+                        {
+                            ws.Cells[currentRow, col + 1].Value = sheetData.Rows[i][col];
+                        }
+                        currentRow++;
+                    }
+
+                    for (int i = start_row - 1; i < end_row && i < sheetData.Rows.Count; i++)
+                    {
+                        for (int col = 0; col < sheetData.Rows[i].Count; col++)
+                        {
+                            ws.Cells[currentRow, col + 1].Value = sheetData.Rows[i][col];
+                        }
+                        currentRow++;
+                    }
+                }
+
+                package.SaveAs(new FileInfo(dest_path));
+            }
+        }
+
+        public (string SheetName, int RowCount) GetSheetWithMostRows(List<ExcelSheetData> data)
+        {
+            string maxSheetName = "";
+            int maxRowCount = 0;
+
+            foreach (var sheet in data)
+            {
+                int rowCount = sheet.Rows.Count;
+                if (rowCount > maxRowCount)
+                {
+                    maxRowCount = rowCount;
+                    maxSheetName = sheet.SheetName;
+                }
+            }
+            return (maxSheetName, maxRowCount);
+        }
+    }
+}