Why ExcelApplication.Workbooks.Count is showing zero even when I have an Excel workbook open

问题

ExcelApplication.Workbooks.Count is showing count = 0 even when I have a document open.

ExcelApplication.Workbooks.Count shows count = 1 when the document opened is not in protected view. But when the opened document is PROTECTED VIEW the ExcelApplication.Workbooks.Count shows 0.

Why the workbook count is 0 in case of protected view excel?

回答1:

Because:

A workbook displayed in a Protected View window is not a member of the Workbooks collection.

If you need to get a handle on a protected workbook:

using (var protectedWorkbook = ExcelApplication.ProtectedViewWindows(1).Workbook)
{
    // do stuff 
}

A robust solution would account for the possible fault condition of multiple ProtectedViewWindows. The above code assumes there is one and only one.

来源：https://stackoverflow.com/questions/58458188/why-excelapplication-workbooks-count-is-showing-zero-even-when-i-have-an-excel-w