EPPlus导入导出不占用进程

导入：

using (ExcelPackage package = new ExcelPackage(new FileStream(openFile.FileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)))
{
    ExcelWorksheet sheet = package.Workbook.Worksheets[1];
    object title = sheet.Cells[3, 1].Value ?? "";
    // do
    int row = 4;
}

导出

using (var package = new ExcelPackage(new FileInfo(sfd.FileName)))
{
    var sheet = package.Workbook.Worksheets.Add("Abc");
    int rowIndex = 1;
    sheet.Cells[rowIndex, 1].Value = "日期";
    sheet.Cells.AutoFitColumns();
    sheet.Cells[1, 1, rowIndex, 12].Style.Border.Left.Style = ExcelBorderStyle.Thin;
    sheet.Cells[1, 1, rowIndex, 12].Style.Border.Top.Style = ExcelBorderStyle.Thin;
    sheet.Cells[1, 1, rowIndex, 12].Style.Border.Right.Style = ExcelBorderStyle.Thin;
    sheet.Cells[1, 1, rowIndex, 12].Style.Border.Bottom.Style = ExcelBorderStyle.Thin;
    package.Save();
    package.Dispose();
}