How to open an Excel document that is already open in MS-Excel?

25 May 20231 minute to read

Syncfusion XlsIO do support opening an Excel document that is already open in Microsoft Excel. But the approaches are different in .NET Framework and .NET Standard.

OpenReadOnly method can be used in .NET Framework whereas FileShare.ReadWrite overload should be used while loading the file into file stream in .NET Standard. The following code snippet explains this.

C# [Cross-platform]

using (ExcelEngine excelEngine = new ExcelEngine())
{
  IApplication application = excelEngine.Excel;
  application.DefaultVersion = ExcelVersion.Excel2016;	
  FileStream inputStream = new FileStream("Template.xlsx", FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
  IWorkbook workbook = application.Workbooks.Open(inputStream);	
  FileStream outputStream = new FileStream("Output.xlsx", FileMode.Create, FileAccess.ReadWrite);
  workbook.SaveAs(outputStream);
}

C# [Windows-specific]

using (ExcelEngine excelEngine = new ExcelEngine())
{
  IApplication application = excelEngine.Excel;
  application.DefaultVersion = ExcelVersion.Excel2016;
  IWorkbook workbook = application.Workbooks.OpenReadOnly("Template.xlsx");
  workbook.SaveAs("Output.xlsx");
}

VB.NET [Windows-specific]

Using excelEngine As ExcelEngine = New ExcelEngine
  Dim application As IApplication = excelEngine.Excel
  application.DefaultVersion = ExcelVersion.Excel2016
  Dim workbook As IWorkbook = application.Workbooks.OpenReadOnly("Template.xlsx")
  workbook.SaveAs("Output.xlsx")
End Using