Open Excel file read only

[rdhasse]

Hello,

Is it possible to support opening an Excel file in read only mode when another user has it open in write mode?

With Excel, this situation will prompt the read only user that the file is locked and still allows them to open it in read only mode to view the content.

We would like to do the same with EPPlus by specifying read only mode such that our C# app can still read the file content.

Thanks,

Randall

[swmal]

Closing this issue since the corresponding support ticket was resolved. Proposed solution:

Extension method

using OfficeOpenXml;
using System.IO;

namespace OfficeOpenXmlExtensions
{
  public enum FileOpenResult
  {
    CanWrite,
    CanOpenReadOnly
  }

  public static class ExcelPackageExtensions
  {
    public static ExcelPackage OpenAndCheckLocked(this ExcelPackage package, string filePath, out FileOpenResult result)
    {
      result = FileOpenResult.CanWrite;
      try
      {
        var s = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
        package.Load(s);
      }
      catch(IOException ex)
      {
        var s = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
        package.Load(s);
        result = FileOpenResult.CanOpenReadOnly;
      }
      return package;
    }
  }
}

Usage

using OfficeOpenXml;
using OfficeOpenXmlExtensions;

ExcelPackage.LicenseContext = LicenseContext.Commercial;

var path = @"c:\Temp\MyExcelFile.xlsx";

using var package = new ExcelPackage();
package.OpenAndCheckLocked(path, out FileOpenResult result);
if(result == FileOpenResult.CanWrite)
{
  package.Save();
}