How do I work with an open Workbook in Excel using ClosedXML (C#)?

Question

I am using ClosedXML to make reports for people in Excel. There are 3 issues that I would like some help with.

1) I have this code here so I can access data from a workbook. It works correctly except for when someone has that workbook open. I don't care if it opens a read only copy, if possible, because all I am doing is accessing information from it.

var WorkbookCopyFrom = new XLWorkbook(WorksheetToCopy);

How can I open it even when someone has it open?

2) In my previous company, I used the Office Interop Nuget package to do something similar. In that package I was able to show the excel file while working on it using this code:

excelApp.Visible = true;

Is there something similar in ClosedXML?

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NickB NickB · Accepted Answer · 2021-05-06T13:23:56

I stumbled on the same problem. A workaround could be opening a FileStream instead of the file directly.

    public void LoadDocumentReadOnly(string fn)
    {
        filename = fn;
        fileStream = new FileStream(fn, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
        Document = new XLWorkbook(fileStream);
    }

How do I work with an open Workbook in Excel using ClosedXML (C#)?

2 Answers