enumerating-excel-com-automation-collections-in-vbnet.md

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title	Enumerating Excel COM Automation collections in VB.NET

When referencing COM Automation collections late-bound, the enumeration via For Each does not automatically work. An explicitly cast or set to a variable of type IEnumerable will work, though:

Dim app As Object = ExcelDnaUtil.Application

Dim sh As Object
Dim flg As Boolean

For Each sh In CType(app.Worksheets, IEnumerable)
    ' Do stuff with sh here
Next

This should not be needed if an interop library is referenced.