使用 SAX Approch Open XML 从行中获取所有单元格

Question

我刚刚使用带有 Open XML SDK 的 DOM 方法读取了一个大 xlsx 文件。它工作正常；但是，这样做需要很长时间。所以我想用 SAX 方法做同样的事情。但是，我对此一无所知。 我在 DOM 方法中所做的是，对于工作簿中的每个工作表，我都会获得工作表的名称。然后我假设第一行包含所有列名。接下来，我动态创建一个类，该类具有第一行中列出的所有属性。之后，我阅读了其余的行。对于每一行，我使用动态创建的自定义类创建一个新对象。然后我遍历行中的每个单元格以使用我得到的值填充对象。

这是我用来完成我刚才描述的使用 DOM 方法的任务的代码。

public static List<Object> ConvertExcelArchiveToListObjects(string filePath)
    {
        ... 
using (SpreadsheetDocument spreadsheetDocument = SpreadsheetDocument.Open(filePath, false))
        {
            WorkbookPart wbPart = spreadsheetDocument.WorkbookPart;
            Sheets theSheets = wbPart.Workbook.Sheets;

            SharedStringTablePart sstPart = spreadsheetDocument.WorkbookPart.GetPartsOfType<SharedStringTablePart>().FirstOrDefault();
            ...
            var sheets = wbPart.Workbook.Sheets.Cast<Sheet>().ToList();

            foreach (WorksheetPart worksheetpart in wbPart.WorksheetParts)
            {
                Worksheet worksheet = worksheetpart.Worksheet;

                string partRelationshipId = wbPart.GetIdOfPart(worksheetpart);
                var correspondingSheet = sheets.FirstOrDefault(
                    s => s.Id.HasValue && s.Id.Value == partRelationshipId);
                Debug.Assert(correspondingSheet != null);
                // Grab the sheet name
                string sheetName = correspondingSheet.GetAttribute("name", "").Value;

                ...

                dynamic expandoObjectClass = new ExpandoObject();
                List<Object> listObjectsCustomClasses  = new List<Object>();
                foreach (var dataRow in rowContent)
                {
                    Type generatedType = typeBuilder.CreateType();
                    object generatedObject = Activator.CreateInstance(generatedType);

                    PropertyInfo[] properties = generatedType.GetProperties();

                    int propertiesCounter = 0;

                    // Loop over the values that we will assign to the properties

                    var rowCells = dataRow.Descendants<Cell>();
                    var value = string.Empty;
                    foreach (var rowCell in rowCells)
                    {
                        if (rowCell.DataType != null
                            && rowCell.DataType.HasValue
                            && rowCell.DataType == CellValues.SharedString
                            && int.Parse(rowCell.CellValue.InnerText) < ssTable.ChildElements.Count)
                        {
                            value = ssTable.ChildElements[int.Parse(rowCell.CellValue.InnerText)].InnerText ?? string.Empty;
                        }
                        else
                        {
                            if (rowCell.CellValue != null && rowCell.CellValue.InnerText != null)
                            {
                                value = rowCell.CellValue.InnerText;
                            }
                            else
                            {
                                value = string.Empty;
                            }
                        }
                        properties[propertiesCounter].SetValue(generatedObject, value, null);
                        propertiesCounter++;
                    }
                    listObjectsCustomClasses.Add(generatedObject);
                }
                listObjects.Add(listObjectsCustomClasses);
            }
        }
        DateTime end = DateTime.UtcNow;
        Console.WriteLine("Measured time: " + (end - begin).TotalMinutes + " minutes.");
        return listObjects;
    }

但是，每当我读取大 xlsx 文件（大小大于 30 MB）时，上述方法都会花费大量时间来执行。我已经编写了这段代码以至少获取行，而无需深入挖掘以获取每行中的单元格。

public static List<Object> ConvertExcelArchiveToListObjectsSAXApproach(string filePath)
    {
        DateTime begin = DateTime.UtcNow;
        List<Object> listObjects = new List<Object>();
        using (SpreadsheetDocument spreadsheetDocument = SpreadsheetDocument.Open(filePath, false))
        {
            WorkbookPart wbPart = spreadsheetDocument.WorkbookPart;
            Sheets theSheets = wbPart.Workbook.Sheets;

            SharedStringTablePart sstPart = spreadsheetDocument.WorkbookPart.GetPartsOfType<SharedStringTablePart>().FirstOrDefault();
            SharedStringTable ssTable = null;
            if (sstPart != null)
                ssTable = sstPart.SharedStringTable;

            // Get the CellFormats for cells without defined data types
            WorkbookStylesPart workbookStylesPart = spreadsheetDocument.WorkbookPart.GetPartsOfType<WorkbookStylesPart>().First();
            CellFormats cellFormats = (CellFormats)workbookStylesPart.Stylesheet.CellFormats;
            var sheets = wbPart.Workbook.Sheets.Cast<Sheet>().ToList();

            foreach (WorksheetPart worksheetpart in wbPart.WorksheetParts)
            {
                //Worksheet worksheet = worksheetpart.Worksheet;
                OpenXmlPartReader reader = new OpenXmlPartReader(worksheetpart);
                bool firstRow = false;

                while (reader.Read())
                {
                    if (reader.ElementType == typeof(Row))
                    {
                       ...
                    }

                    if (reader.ElementType != typeof(Worksheet)) // Dont' want to skip the contents of the worksheet
                        reader.Skip(); // Skip contents of any node before finding the first row.
                }    DateTime end = DateTime.UtcNow;
        Console.WriteLine("Measured time: " + (end - begin).TotalMinutes + " minutes.");
        return listObjects;
    }

但是，我在里面设置的断点

if (reader.ElementType == typeof(Row))
                    {
                       ...
                    } 

甚至没有被击中。关于我缺少什么的任何想法？谢谢！

Answer 1

你看到线程Using OpenXmlReader中的代码了吗？代码正在做你想做的事。