如何使用 epplus 遍历 Excel 表中的行？

Question

我是 epplus 的新手，我正在尝试从 Excel 表中读取一些值。

这是我目前所拥有的：

var fileInfo = new FileInfo(filename);
using(var excelPackage = new OfficeOpenXml.ExcelPackage(fileInfo))
{
    foreach (var sheet in excelPackage.Workbook.Worksheets)
    {
        foreach (ExcelTable table in sheet.Tables)
        {
             foreach(var row in table.Rows)  // <-- !!
             { ... }
        }
    }
}

但是，现在我被难住了，因为 ExcelTable 只有一个 Columns 属性，但没有我预期的 Rows 属性。我在库中的任何对象上都找不到 Rows 属性。

如何遍历表格，逐行读取？

Answer 1

在寻找相同问题的帮助时，我偶然发现了这个link。它当然对我有用！绝对比使用互操作对象更好。 :)

我稍微调整了一下：

var package = new ExcelPackage(new FileInfo("sample.xlsx"));

ExcelWorksheet workSheet = package.Workbook.Worksheets[0];
var start = workSheet.Dimension.Start;
var end = workSheet.Dimension.End;
for (int row = start.Row; row <= end.Row; row++)
{ // Row by row...
    for (int col = start.Column; col <= end.Column; col++)
    { // ... Cell by cell...
        object cellValue = workSheet.Cells[row, col].Text; // This got me the actual value I needed.
    }
}

Answer 2

这是一种将完整行作为ExcelRange 的方法，然后可以对其进行迭代或用于 LINQ：

for (var rowNum = 1; rowNum <= sheet.Dimension.End.Row; rowNum++)
{
    var row = sheet.Cells[string.Format("{0}:{0}", rowNum)];
    // just an example, you want to know if all cells of this row are empty
    bool allEmpty = row.All(c => string.IsNullOrWhiteSpace(c.Text));
    if (allEmpty) continue; // skip this row
    // ...
}

Answer 3

您可以访问表格的.Worksheet 属性并为其单元格编制索引。为此，我编写了一个扩展方法，它生成了一系列将列名映射到单元格值的字典：

public static IEnumerable<IDictionary<string, object>> GetRows(this ExcelTable table)
{
    var addr = table.Address;
    var cells = table.WorkSheet.Cells;

    var firstCol = addr.Start.Column;

    var firstRow = addr.Start.Row;
    if (table.ShowHeader)
        firstRow++;
    var lastRow = addr.End.Row;

    for (int r = firstRow; r <= lastRow; r++)
    {
        yield return Enumerable.Range(0, table.Columns.Count)
            .ToDictionary(x => table.Columns[x].Name, x => cells[r, firstCol + x].Value);
    }
}

Answer 4

我遇到了同样的问题，我使用ExcelTable 来获取表格边界并使用ExcelWorksheet 来检索数据来解决它。所以你的代码看起来像这样：

var fileInfo = new FileInfo(filename);
using(var excelPackage = new OfficeOpenXml.ExcelPackage(fileInfo))
{
    foreach (var sheet in excelPackage.Workbook.Worksheets)
    {
        foreach (ExcelTable table in sheet.Tables)
        {
            ExcelCellAddress start = table.Address.Start;
            ExcelCellAddress end = table.Address.End;

            for (int row = start.Row; row <= end.Row; ++row)
            {
                ExcelRange range = sheet.Cells[row, start.Column, row, end.Column];
                ...
            }
        }
    }
}

您需要检查表头或其他内容，但这对我有用。

Answer 5

我还试图弄清楚如何正确地遍历对象并使用此 API 获取我需要的数据。

我从各种帖子和作者的入门页面收集信息，并将它们放在一起以帮助自己和他人。

主要问题是迭代的入口点。我见过的大多数解决方案都在工作表之后，而这个问题在表格中是特定的，我对这两个问题都很好奇，所以我在这两个问题上都展示了我的发现。

工作表示例：

using (var package = new ExcelPackage(new FileInfo(file)))
{
    //what i've seen used the most, entry point is the worksheet not the table w/i the worksheet(s)
    using (var worksheet = package.Workbook.Worksheets.FirstOrDefault())
    {
        if (worksheet != null)
        {
            for (int rowIndex = worksheet.Dimension.Start.Row; rowIndex <= worksheet.Dimension.End.Row; rowIndex++)
            {
                var row = worksheet.Row(rowIndex);
                //from comments here... https://github.com/JanKallman/EPPlus/wiki/Addressing-a-worksheet
                //#:# gets entire row, A:A gets entire column
                var rowCells = worksheet.Cells[$"{rowIndex}:{rowIndex}"];
                //returns System.Object[,]
                //type is string so it likely detects many cells and doesn't know how you want the many formatted together...
                var rowCellsText = rowCells.Text;
                var rowCellsTextMany = string.Join(", ", rowCells.Select(x => x.Text));
                var allEmptyColumnsInRow = rowCells.All(x => string.IsNullOrWhiteSpace(x.Text));
                var firstCellInRowWithText = rowCells.Where(x => !string.IsNullOrWhiteSpace(x.Text)).FirstOrDefault();
                var firstCellInRowWithTextText = firstCellInRowWithText?.Text;
                var firstCellFromRow = rowCells[rowIndex, worksheet.Dimension.Start.Column];
                var firstCellFromRowText = firstCellFromRow.Text;
                //throws exception...
                //var badRow = rowCells[worksheet.Dimension.Start.Row - 1, worksheet.Dimension.Start.Column - 1];

                //for me this happened on row1 + row2 beign merged together for the column headers
                //not sure why the row.merged property is false for both rows though
                if (allEmptyColumnsInRow)
                    continue;

                for (int columnIndex = worksheet.Dimension.Start.Column; columnIndex <= worksheet.Dimension.End.Column; columnIndex++)
                {
                    var column = worksheet.Column(columnIndex);
                    var currentRowColumn = worksheet.Cells[rowIndex, columnIndex];
                    var currentRowColumnText = currentRowColumn.Text;
                    var currentRowColumnAddress = currentRowColumn.Address;
                    //likely won't need to do this, but i wanted to show you can tangent off at any level w/ that info via another call
                    //similar to row, doing A:A or B:B here, address is A# so just get first char from address
                    var columnCells = worksheet.Cells[$"{currentRowColumnAddress[0]}:{currentRowColumnAddress[0]}"];
                    var columnCellsTextMany = string.Join(", ", columnCells.Select(x => x.Text));
                    var allEmptyRowsInColumn = columnCells.All(x => string.IsNullOrWhiteSpace(x.Text));
                    var firstCellInColumnWithText = columnCells.Where(x => !string.IsNullOrWhiteSpace(x.Text)).FirstOrDefault();
                    var firstCellInColumnWithTextText = firstCellInColumnWithText?.Text;
                }
            }
        }
    }
}

现在事情可能会有些混乱，至少对我来说，我没有桌子可以开始。在同一个包 using 语句下，如果我首先遍历工作表单元格，然后使用 Tables 属性触摸任何内容，则会引发异常。如果我重新实例化一个包并使用相同/相似的代码，则在查看我们是否有任何表格时它不会爆炸。

表格示例：

//for some reason, if i don't instantiating another package and i work with the 'Tables' property in any way, the API throws a...
//Object reference not set to an instance of an object.
//at OfficeOpenXml.ExcelWorksheet.get_Tables()
//excetion... this is because i have data in my worksheet but not an actual 'table' (Excel => Insert => Table)
//a parital load of worksheet cell data + invoke to get non-existing tables must have a bug as below code does not
//throw an exception and detects null gracefully on firstordefault
using (var package = new ExcelPackage(new FileInfo(file)))
{
    //however, question was about a table, so lets also look at that... should be the same?
    //no IDisposable? :(
    //adding a table manually to my worksheet allows the 'same-ish' (child.Parent, aka table.WorkSheet) code to iterate
    var table = package.Workbook.Worksheets.SelectMany(x => x.Tables).FirstOrDefault();

    if (table != null)
    {
        for (int rowIndex = table.Address.Start.Row; rowIndex <= table.Address.End.Row; rowIndex++)
        {
            var row = table.WorkSheet.Row(rowIndex);

            var rowCells = table.WorkSheet.Cells[$"{rowIndex}:{rowIndex}"];
            var rowCellsManyText = string.Join(", ", rowCells.Select(x => x.Text));

            for (int columnIndex = table.Address.Start.Column; columnIndex <= table.Address.End.Column; columnIndex++)
            {
                var currentRowColumn = table.WorkSheet.Cells[rowIndex, columnIndex];
                var currentRowColumnText = currentRowColumn.Text;
            }
        }
    }
}

基本上一切工作和运作方式都相同，您只需要关注 child.Parent，AKA table.WorkSheet 即可获得相同的东西。正如其他人所提到的，扩展方法甚至可能的包装类可以根据您的业务需求的具体情况为您提供更多粒度，但这不是这个问题的目的。

关于索引 cmets 和响应，我建议坚持使用“行”和“列”属性，例如 first、last、for、foreach 等，而不是硬编码索引与非索引基本属性，至少在新版本的情况下，我在这里没有问题。

Answer 6

我不确定 epplus，但我想我会快速建议使用 LinqToExcel

var excel = new ExcelQueryFactory(excel);

var info = excel.Worksheet("Sheet1")
                .Select(z=> new
                     {
                      Name = row["Name"].Cast<string>(),
                      Age = row["Age"].Cast<int>(),
                     }).ToList();

你可以从 NuGet 获取它

Install-Package LinqToExcel