c#利用NPOI读取Excel转为DataTable

不多说直接上代码

代码参考自网络

/// 

/// xxc定制优化后
/// Excel导入成Datable
/// 
/// 导入路径(包含文件名与扩展名)
/// 
public static DataTable ExcelToTable(string file)
{
    try
    {
        DataTable dt = new DataTable();
        IWorkbook workbook;
        string fileExt = Path.GetExtension(file).ToLower();
        using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
        {
            //XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
            if (fileExt == ".xlsx") { workbook = new XSSFWorkbook(fs); } else if (fileExt == ".xls") { workbook = new HSSFWorkbook(fs); } else { workbook = null; }
            if (workbook == null) { return null; }
            ISheet sheet = workbook.GetSheetAt(0);

            //表头  
            IRow header = sheet.GetRow(sheet.FirstRowNum);
            List<int> columns = new List<int>();
            for (int i = 0; i < header.LastCellNum; i++)
            {
                object obj = GetValueType(file, workbook, header.GetCell(i));
                if (obj == null || obj.ToString() == string.Empty)
                {
                    //xxc20220613遇空列，停止读取列
                    break;
                    //dt.Columns.Add(new DataColumn("Columns" + i.ToString()));
                }
                else
                    dt.Columns.Add(new DataColumn(obj.ToString()));
                columns.Add(i);
            }
            //数据  
            for (int i = sheet.FirstRowNum + 1; i <= sheet.LastRowNum; i++)
            {
                DataRow dr = dt.NewRow();
                bool hasValue = false;
                foreach (int j in columns)
                {
                    try
                    {
                        dr[j] = GetValueType(file, workbook, sheet.GetRow(i).GetCell(j));
                        if (dr[j] != null && dr[j].ToString() != string.Empty)
                        {
                            hasValue = true;
                        }
                    }
                    catch (Exception ee)
                    {
                        continue;
                    }

                }

                if (hasValue)
                {
                    dt.Rows.Add(dr);
                }
                else
                {
                    //xxc20220613遇空行，停止读取行
                    break;
                }
            }
        }
        return dt;
    }
    catch (Exception e)
    {
        return null;
    }

}





/// 

        /// 获取单元格类型
        /// 
        /// 
        /// 
private static object GetValueType(string strFileName, IWorkbook workbook, ICell cell)
{
    if (cell == null)
        return null;
    switch (cell.CellType)
    {
        case CellType.Blank: //BLANK:  
            return null;
        case CellType.Boolean: //BOOLEAN:  
            return cell.BooleanCellValue;
        case CellType.Numeric: //NUMERIC:  
            return cell.NumericCellValue;
        case CellType.String: //STRING:  
            return cell.StringCellValue;
        case CellType.Error: //ERROR:  
            return cell.ErrorCellValue;
        case CellType.Formula: //FORMULA:
            object rv = null;
            if (Path.GetExtension(strFileName).ToLower().Trim() == ".xlsx")
            {
                XSSFFormulaEvaluator eva = new XSSFFormulaEvaluator(workbook);
                if (eva.Evaluate(cell).CellType == CellType.Numeric)
                {
                    rv = eva.Evaluate(cell).NumberValue;
                }
                else
                {
                    rv = eva.Evaluate(cell).StringValue;
                }
            }
            else
            {
                HSSFFormulaEvaluator eva = new HSSFFormulaEvaluator(workbook);
                if (eva.Evaluate(cell).CellType == CellType.Numeric)
                {
                    rv = eva.Evaluate(cell).NumberValue;
                }
                else
                {
                    rv = eva.Evaluate(cell).StringValue;
                }
            }
            return rv;
        default:
            return "=" + cell.CellFormula;
    }
}