.net core使用IExcelDataReader读取Excel

 通过读取文件的方式：

FileStream stream = File.Open(filePath, FileMode.Open, FileAccess.Read);
IExcelDataReader excelReader;

//1. Reading Excel file
if (Path.GetExtension(filePath).ToUpper() == ".XLS")
{
    //1.1 Reading from a binary Excel file ('97-2003 format; *.xls)
    excelReader = ExcelReaderFactory.CreateBinaryReader(stream);
}
else
{
    //1.2 Reading from a OpenXml Excel file (2007 format; *.xlsx)
    excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream);
}

//2. DataSet - The result of each spreadsheet will be created in the result.Tables
DataSet result = excelReader.AsDataSet();

//3. DataSet - Create column names from first row
excelReader.IsFirstRowAsColumnNames = false;

 通过文件流：

public object UploadExcel(IFormFile file)
        {

            try
            {
                MemoryStream target = new MemoryStream();
                file.OpenReadStream().CopyTo(target);
                byte[] data = target.ToArray();
                Stream stream = new MemoryStream(data);//excel文件转成数据流
                var excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream);//流数据转成Excelreader
                //Excelreader转成datatable
                var dataSet = excelReader.AsDataSet(new ExcelDataSetConfiguration
                {
                    ConfigureDataTable = _ => new ExcelDataTableConfiguration
                    {
                        UseHeaderRow = true // Use first row is ColumnName here :D
                    }
                });
                if (dataSet.Tables.Count > 0)
                {
                    var dtData = dataSet.Tables[0];

                }
            }
            catch (Exception ex)
            {
                
            }
      
        }