一、Excel导出帮助类 /*引用NuGet包 EPPlus*/
/*引用NuGet包 EPPlus*/ /// <summary> /// Excel导出帮助类 /// </summary> public class ExcelExportHelper { public static string ExcelContentType => "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"; /// <summary> /// List转DataTable /// </summary> /// <typeparam name="T"></typeparam> /// <param name="data"></param> /// <returns></returns> public static DataTable ListToDataTable<T>(List<T> data) { PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(typeof(T)); DataTable dataTable = new DataTable(); for (int i = 0; i < properties.Count; i++) { PropertyDescriptor property = properties[i]; dataTable.Columns.Add(property.Name, Nullable.GetUnderlyingType(property.PropertyType) ?? property.PropertyType); } object[] values = new object[properties.Count]; foreach (T item in data) { for (int i = 0; i < values.Length; i++) { values[i] = properties[i].GetValue(item); } dataTable.Rows.Add(values); } return dataTable; } /// <summary> /// 导出Excel /// </summary> /// <param name="dataTable">数据源</param> /// <param name="heading">工作簿Worksheet</param> /// <param name="showSrNo">//是否显示行编号</param> /// <param name="columnsToTake">要导出的列</param> /// <returns></returns> public static byte[] ExportExcel(DataTable dataTable, string heading = "", bool showSrNo = false, params string[] columnsToTake) { byte[] result; using (ExcelPackage package = new ExcelPackage()) { ExcelWorksheet workSheet = package.Workbook.Worksheets.Add($"{heading}Data"); int startRowFrom = string.IsNullOrEmpty(heading) ? 1 : 3; //开始的行 //是否显示行编号 if (showSrNo) { DataColumn dataColumn = dataTable.Columns.Add("#", typeof(int)); dataColumn.SetOrdinal(0); int index = 1; foreach (DataRow item in dataTable.Rows) { item[0] = index; index++; } } //Add Content Into the Excel File workSheet.Cells["A" + startRowFrom].LoadFromDataTable(dataTable, true); // autofit width of cells with small content int columnIndex = 1; foreach (DataColumn item in dataTable.Columns) { if (item.DataType == typeof(DateTime)) { var i = dataTable.Columns.IndexOf(item); //设置列格式为自定义 "yyyy/MM/dd HH:mm:ss" workSheet.Cells[2, i + 1, dataTable.Rows.Count + 1, i + 1].Style.Numberformat.Format = "yyyy/MM/dd HH:mm"; } ExcelRange columnCells = workSheet.Cells[workSheet.Dimension.Start.Row, columnIndex, workSheet.Dimension.End.Row, columnIndex]; int maxLength = columnCells.Max(cell => cell.Value == null || cell.Value is DBNull || string.IsNullOrEmpty(cell.Value.ToString()) ? 0 : cell.Value.ToString().Count()); if (maxLength < 150) { workSheet.Column(columnIndex).AutoFit(); } columnIndex++; } // format header - bold, yellow on black using (ExcelRange r = workSheet.Cells[startRowFrom, 1, startRowFrom, dataTable.Columns.Count]) { r.Style.Font.Color.SetColor(System.Drawing.Color.White); r.Style.Font.Bold = true; r.Style.Fill.PatternType = ExcelFillStyle.Solid; r.Style.Fill.BackgroundColor.SetColor(System.Drawing.ColorTranslator.FromHtml("#1fb5ad")); } // format cells - add borders using (ExcelRange r = workSheet.Cells[startRowFrom + 1, 1, startRowFrom + dataTable.Rows.Count, dataTable.Columns.Count]) { r.Style.Border.Top.Style = ExcelBorderStyle.Thin; r.Style.Border.Bottom.Style = ExcelBorderStyle.Thin; r.Style.Border.Left.Style = ExcelBorderStyle.Thin; r.Style.Border.Right.Style = ExcelBorderStyle.Thin; r.Style.Border.Top.Color.SetColor(System.Drawing.Color.Black); r.Style.Border.Bottom.Color.SetColor(System.Drawing.Color.Black); r.Style.Border.Left.Color.SetColor(System.Drawing.Color.Black); r.Style.Border.Right.Color.SetColor(System.Drawing.Color.Black); } // removed ignored columns for (int i = dataTable.Columns.Count - 1; i >= 0; i--) { if (i == 0 && showSrNo) { continue; } if (!columnsToTake.Contains(dataTable.Columns[i].ColumnName)) { workSheet.DeleteColumn(i + 1); } } if (!string.IsNullOrEmpty(heading)) { workSheet.Cells["A1"].Value = heading; workSheet.Cells["A1"].Style.Font.Size = 20; workSheet.InsertColumn(1, 1); workSheet.InsertRow(1, 1); workSheet.Column(1).Width = 5; } result = package.GetAsByteArray(); } return result; } /// <summary> /// 导出Excel /// </summary> /// <typeparam name="T"></typeparam> /// <param name="data"></param> /// <param name="heading"></param> /// <param name="isShowSlNo"></param> /// <param name="columnsToTake"></param> /// <returns></returns> public static byte[] ExportExcel<T>(List<T> data, string heading = "", bool isShowSlNo = false, params string[] columnsToTake) { return ExportExcel(ListToDataTable(data), heading, isShowSlNo, columnsToTake); } }
二、调用
执行后Excel将会保存到D盘
string strSql = string.Format(@"SELECT TOP 10 [Name] AS 姓名,[PhoneNumber] AS 手机,[Email] AS 邮箱,[Department] AS 部门 FROM [User]"); DataTable dt = DBHelper.ExecuteTable(strSql); string[] columns = { "姓名", "手机", "邮箱", "部门" }; byte[] filecontent = ExcelExportHelper.ExportExcel(dt, "", false, columns); FileStream fs = new FileStream(@"D:信息.xlsx", FileMode.Create, FileAccess.Write); fs.Write(filecontent, 0, filecontent.Length); fs.Flush(); fs.Close();