如何减less程序执行时间，提高整体性能？
我已经创build了一个Windows应用程序来处理一个文件夹中的一组excel文件，从它们中寻找一些select性的信息。 之后，它将所有这些信息存储到一个新的Excel表单中。 这是一种报告生成工具。 我正在努力减less这个应用程序的总体执行时间。 目前，总共需要大约45-50秒完成一个成功执行周期。 代码与此类似：
PS由于限制政策，我无法分享实际的代码。 但是下面显示的代码足以提供一些解决scheme。
#region master_tracking_sheet public string[] xlsfiles; public string[] personList = new string[35]; public string[,] excelSheet_det = new string[35, 6]; private void buttonBrowseFolder_Click(object sender, EventArgs e) { if (folder_browse_excelSheet.ShowDialog() == DialogResult.OK) { this.txt_DirPath.Text = folder_browse_excelSheet.SelectedPath; gotFile = true; } } private void btnCreateMasterSheet_Click(object sender, EventArgs e) { try { if (gotFile == false) { MessageBox.Show("Please select a folder first!"); } else { var extensions = new HashSet<string>(StringComparer.OrdinalIgnoreCase) { ".xls", ".xlsx", }; userNotifier = false; var baseDir = txt_DirPath.Text; var file_count = Directory.EnumerateFiles(baseDir).Count(filename => extensions.Contains(Path.GetExtension(filename))); Excel.Application application = new Excel.Application(); xlsfiles = Directory.GetFiles(folder_browse_excelSheet.SelectedPath, "*.xls"); for (int j = 1; j <= file_count; j++) //Generating list of persons whose excelSheets are there { csvFilePath = System.IO.Path.GetFileNameWithoutExtension(xlsfiles[j - 1]); personList[j - 1] = csvFilePath.ToString(); } bool check_proceed = checkpersonSheetExist(personList);//Check for any missing excelSheet file as per the given person list if (check_proceed == false) { application.Quit(); killApplication(true); } else { for (int i = 1; i <= file_count; i++) { Excel.Workbook temp_wb; excelSheet_det[i - 1, 0] = personList[i - 1].ToString(); //Adding person name as first entry string excelFileName = xlsfiles[i - 1]; excelFilePath = excelFileName; //reassigning the excelFilePath to make an entry in excelSheet Log.txt findWordInFile("Non Working", excelFileName); //Calling the method to identify Non-working entry if any //The above method sets flag value to 'y' if true else the flag value remains to 'n' temp_wb = application.Workbooks.Open(excelFileName); Excel.Worksheet worksheet; worksheet = temp_wb.Sheets[1]; var cell_val = 0.0; var cell_valA = 0.0; if ((worksheet.Cells[5, 25] as Excel.Range).Value == null || (worksheet.Cells[5, 25] as Excel.Range).Value == 0) cell_val = 0; else cell_val = (double)(worksheet.Cells[5, 25] as Excel.Range).Value; if ((worksheet.Cells[4, 25] as Excel.Range).Value == null || (worksheet.Cells[4, 25] as Excel.Range).Value==0) cell_valA = 0; else cell_valA = (double)(worksheet.Cells[4, 25] as Excel.Range).Value; if (cell_val == 0) { excelSheet_det[i - 1, 1] = cell_valA.ToString(); //Adding Normal Hours } else { excelSheet_det[i - 1, 1] = cell_val.ToString(); //Adding Normal Hours } if (flag == 'y') //if non-working non billable entry found { var cell_val1 = 0.0; if ((worksheet.Cells[14, 25] as Excel.Range).Value == null || (worksheet.Cells[14, 25] as Excel.Range).Value == 0.0) cell_val1 = 0; else cell_val1 = (double)(worksheet.Cells[14, 25] as Excel.Range).Value; excelSheet_det[i - 1, 3] = cell_val1.ToString();//Adding Non-working Hours excelSheet_det[i - 1, 2] = "0"; //Setting working hours to zero } else //if non-working non billable entry NOT found { var cell_val2 = 0.0; if ((worksheet.Cells[14, 25] as Excel.Range).Value == null || (worksheet.Cells[14, 25] as Excel.Range).Value == 0) cell_val2 = 0; else cell_val2 = (double)(worksheet.Cells[14, 25] as Excel.Range).Value; excelSheet_det[i - 1, 2] = cell_val2.ToString();//Adding working Hours excelSheet_det[i - 1, 3] = "0"; //Setting non-working hours to zero } var cell_val3 = 0.0; var cell_val3_1 = 0.0; var cell_val3_2 = 0.0; if ((worksheet.Cells[15, 25] as Excel.Range).Value == null || (worksheet.Cells[15, 25] as Excel.Range).Value == 0) cell_val3 = 0; else cell_val3 = (double)(worksheet.Cells[15, 25] as Excel.Range).Value; if ((worksheet.Cells[13, 25] as Excel.Range).Value == null || (worksheet.Cells[13, 25] as Excel.Range).Value == 0) cell_val3_1 = 0; else cell_val3_1 = (double)(worksheet.Cells[13, 25] as Excel.Range).Value; if ((worksheet.Cells[12, 25] as Excel.Range).Value == null || (worksheet.Cells[12, 25] as Excel.Range).Value == 0) cell_val3_2 = 0; else cell_val3_2 = (double)(worksheet.Cells[12, 25] as Excel.Range).Value; if (cell_val3 == 0 && cell_val3_1 == 0) { excelSheet_det[i - 1, 4] = cell_val3_2.ToString(); } else if (cell_val3_1 == 0 && cell_val3_2 == 0) { excelSheet_det[i - 1, 4] = cell_val3.ToString(); } else { excelSheet_det[i - 1, 4] = cell_val3_1.ToString(); } var cell_val4 = DateTime.MinValue; if ((worksheet.Cells[3, 24] as Excel.Range).Value == null) cell_val4 = DateTime.MinValue; else cell_val4 = (worksheet.Cells[3, 24] as Excel.Range).Value; excelSheet_det[i - 1, 5] = cell_val4.ToString();//copy last date of excelSheet entry Marshal.ReleaseComObject(temp_wb); } application.Workbooks.Close(); application.Quit(); } /*Writing the array contents into the excel master sheet*/ string masterSheetPath = folder_browse_excelSheet.SelectedPath + "\\Master Spreadsheet\\" + "MasterSheet.xls"; if (!Directory.Exists(folder_browse_excelSheet.SelectedPath + "\\masterSheet")) { Directory.CreateDirectory(folder_browse_excelSheet.SelectedPath + "\\Master Spreadsheet"); } if (!File.Exists(masterSheetPath)) { FileStream fs = File.Create(masterSheetPath); fs.Close(); } Excel.Application excel = new Excel.Application(); Excel.Workbook workBook = excel.Workbooks.Open(masterSheetPath); Excel.Worksheet sheet = workBook.ActiveSheet; int numRows = sheet.UsedRange.Rows.Count; //MessageBox.Show(numRows.ToString()); //Check for any duplicate entries in the mastersheet string masterDupErrDisplay = string.Empty; if (numRows > 1) { for (int i1 = 0; i1 < xlsfiles.Length; i1++) { for (int ch = 0; ch < numRows; ch++) { if (excelSheet_det[i1, 5] == (((sheet.Cells[ch + 1, 6] as Excel.Range).Value)).ToString() && excelSheet_det[i1, 0] == ((string)(sheet.Cells[ch + 1, 1] as Excel.Range).Value)) { if (!masterDupErrDisplay.Contains(excelSheet_det[i1, 0].ToString())) { masterDupErrDisplay += string.Join(Environment.NewLine, excelSheet_det[i1, 0].ToString()); masterDupErrDisplay += string.Join(Environment.NewLine, Environment.NewLine); } } } } if (masterDupErrDisplay != null) { if (MessageBox.Show("Duplicate entries have been found for these people " + Environment.NewLine + masterDupErrDisplay + Environment.NewLine + "Do you wish to Continue?", "Duplicate Mastersheet entry Error", MessageBoxButtons.YesNo) == DialogResult.No) { excel.Quit(); killApplication(true); } } } sheet.Cells[1, 1] = "Name"; sheet.Cells[1, 2] = "Normal Hours"; sheet.Cells[1, 3] = "Working Hours"; sheet.Cells[1, 4] = "Not working Hours"; sheet.Cells[1, 5] = "Total Hours"; sheet.Cells[1, 6] = "excelSheet Stamp"; for (int i = 0; i < xlsfiles.Length; i++) { sheet.Cells[numRows + 1 + i, 1] = excelSheet_det[i, 0]; sheet.Cells[numRows + 1 + i, 2] = excelSheet_det[i, 1]; sheet.Cells[numRows + 1 + i, 3] = excelSheet_det[i, 2]; sheet.Cells[numRows + 1 + i, 4] = excelSheet_det[i, 3]; sheet.Cells[numRows + 1 + i, 5] = excelSheet_det[i, 4]; sheet.Cells[numRows + 1 + i, 6] = excelSheet_det[i, 5]; } workBook.RefreshAll(); excel.Calculate(); workBook.Save(); workBook.Close(true); excel.Workbooks.Close(); excel.Quit(); application.Quit(); MessageBox.Show("Master track sheet is successfully updated!", "Process Successful"); } } catch (Exception ex) { throw ex; } } #endregion master_tracking_sheet public bool checkpersonSheetExist(string[] assocName) { try { string[,] personListSupply = new string[35, 2]; int counter = 0; string errorDisplay = string.Empty; string line; // Read the file and display it line by line. System.IO.StreamReader file = new System.IO.StreamReader(folder_browse_excelSheet.SelectedPath + "\\team_members.txt"); while ((line = file.ReadLine()) != null) { personListSupply[counter, 0] = line.ToString(); personListSupply[counter, 1] = "n"; counter++; } file.Close(); int c = 0; while (assocName[c] != null) { c++; } for (int i = 0; i < counter; i++) { for (int k = 0; k < c; k++) { if (personListSupply[i, 0] == assocName[k]) { personListSupply[i, 1] = "y"; continue; } } if (personListSupply[i, 1] == "n") { errorDisplay += string.Join(Environment.NewLine, personListSupply[i, 0].ToString()); errorDisplay += string.Join(Environment.NewLine, Environment.NewLine); } } if (MessageBox.Show("The excel files are missing for" + Environment.NewLine + errorDisplay + Environment.NewLine + "Do you wish to Continue?", "File Missing Error", MessageBoxButtons.YesNo) == DialogResult.Yes) { return true; } else { return false; } } catch (Exception ex) { throw ex; } } 我会去一些商业或开源.NET Excel库，如SpreadsheetLight ，它允许直接创buildxls和xslx文件没有基于UI的Excel应用程序。
你也应该看看OpenXML 。
有很多事情你可以做
1.你可以提高你的代码质量（添加logging器语句，找出哪个函数需要花费时间进行debugging，如果可能的话，改进它）
2.使用比“沉重而易用”的数据结构和function更less的数据结构。 （这确实提高了性能）
3.删除不需要的代码并保存不需要的I / O操作（每次从文件中读取，取而代之的是对其执行操作，这也提高了性能）
如果可能使用multithreading，我不是C＃的人，但如果可能的话使用线程。 这将提高性能肯定有明显的收益（如果在你的情况下可能的并发文件操作，如果你有很高的CPU功率，那么试试这个）
我可以想到一些事情来加速这一点，但我把你提交给Excel Interop的链接- 效率和性能是最好的之一。
如果你真的想要速度，你可以：
- 使用OpenXML来避免Interop开销
- 不要声明Excel和/或多个工作簿variables的两个实例
- 在处理的同时closuresExcel更新UI
编辑：尝试closuresScreenUpdating并将计算设置为手动（以避免任何后续的Excel计算 – 如果有任何公式引用您要更新的单元格）：
private static XlCalculation xlCalculation = XlCalculation.xlCalculationAutomatic; static public void TurnOffApplicationSettings(Excel.Application xlApp) { xlApp.ScreenUpdating = false; xlApp.DisplayAlerts = false; xlCalculation = xlApp.Calculation; //Record the current Calculation Mode xlApp.Calculation = XlCalculation.xlCalculationManual; xlApp.UserControl = false; xlApp.EnableEvents = false; }
然后运行您的长时间操作并将设置恢复为真，并将计算恢复为自动（或更正确地说是之前设置的）：
static public void TurnOnApplicationSettings(Excel.Application xlApp) { xlApp.ScreenUpdating = true; xlApp.DisplayAlerts = true; xlApp.Calculation = xlCalculation; xlApp.UserControl = true; xlApp.EnableEvents = true; }