使用NPOI将Excel导出到DataTable

Question

我想使用NPOI读取Excel Tables 2010 xlsx,然后将数据导出到DataTables但不知道如何使用它.任何人都可以一步一步地告诉我如何将Excel导出到Datatable？我已经下载了NPOI.dll,添加到参考但不知道还有什么...

Answer 1

以下是使用NPOI将Excel文件转换为DataSet的最小代码:

IWorkbook workbook;
using (FileStream stream = new FileStream(excelFilePath, FileMode.Open, FileAccess.Read))
{
    workbook = new HSSFWorkbook(stream);
}

ISheet sheet = workbook.GetSheetAt(0); // zero-based index of your target sheet
DataTable dt = new DataTable(sheet.SheetName);

// write header row
IRow headerRow = sheet.GetRow(0);
foreach (ICell headerCell in headerRow)
{
    dt.Columns.Add(headerCell.ToString());
}

// write the rest
int rowIndex = 0;
foreach (IRow row in sheet)
{
    // skip header row
    if (rowIndex++ == 0) continue;
    DataRow dataRow = dt.NewRow();
    dataRow.ItemArray = row.Cells.Select(c => c.ToString()).ToArray();
    dt.Rows.Add(dataRow);
}

Answer 2

private static ISheet GetFileStream(string fullFilePath)
{
    var fileExtension = Path.GetExtension(fullFilePath);
    string sheetName;
    ISheet sheet = null;
    switch (fileExtension)
    {
        case ".xlsx":
            using (var fs = new FileStream(fullFilePath, FileMode.Open, FileAccess.Read))
            {
                var wb = new XSSFWorkbook(fs);
                sheetName = wb.GetSheetAt(0).SheetName;
                sheet = (XSSFSheet) wb.GetSheet(sheetName);
            }
            break;
        case ".xls":
            using (var fs = new FileStream(fullFilePath, FileMode.Open, FileAccess.Read))
            {
                var wb = new HSSFWorkbook(fs);
                sheetName = wb.GetSheetAt(0).SheetName;
                sheet = (HSSFSheet) wb.GetSheet(sheetName);
            }
            break;
    }
    return sheet;
}

private static DataTable GetRequestsDataFromExcel(string fullFilePath)
{
    try
    {
        var sh = GetFileStream(fullFilePath);
        var dtExcelTable = new DataTable();
        dtExcelTable.Rows.Clear();
        dtExcelTable.Columns.Clear();
        var headerRow = sh.GetRow(0);
        int colCount = headerRow.LastCellNum;
        for (var c = 0; c < colCount; c++)
            dtExcelTable.Columns.Add(headerRow.GetCell(c).ToString());
        var i = 1;
        var currentRow = sh.GetRow(i);
        while (currentRow != null)
        {
            var dr = dtExcelTable.NewRow();
            for (var j = 0; j < currentRow.Cells.Count; j++)
            {
                var cell = currentRow.GetCell(j);

                if (cell != null)
                    switch (cell.CellType)
                    {
                        case CellType.Numeric:
                            dr[j] = DateUtil.IsCellDateFormatted(cell)
                                ? cell.DateCellValue.ToString(CultureInfo.InvariantCulture)
                                : cell.NumericCellValue.ToString(CultureInfo.InvariantCulture);
                            break;
                        case CellType.String:
                            dr[j] = cell.StringCellValue;
                            break;
                        case CellType.Blank:
                            dr[j] = string.Empty;
                            break;
                    }
            }
            dtExcelTable.Rows.Add(dr);
            i++;
            currentRow = sh.GetRow(i);
        }
        return dtExcelTable;
    }
    catch (Exception e)
    {
        throw;
    }
}

Answer 3

在Codeplex 网站的下载部分有example package一个 C# 示例包。如果你还没有尝试过的话。

这是最简单的例子 -

using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;

//.....

private void button1_Click(object sender, EventArgs e)
{
    HSSFWorkbook hssfwb;
    using (FileStream file = new FileStream(@"c:\test.xls", FileMode.Open, FileAccess.Read))
    {
        hssfwb= new HSSFWorkbook(file);
    }

    ISheet sheet = hssfwb.GetSheet("Arkusz1");
    for (int row = 0; row <= sheet.LastRowNum; row++)
    {
        if (sheet.GetRow(row) != null) //null is when the row only contains empty cells 
        {
            MessageBox.Show(string.Format("Row {0} = {1}", row, sheet.GetRow(row).GetCell(0).StringCellValue));
        }
    }
}