使用Application.Intersect为什么我会得到类型不匹配

Question

Here is my code. I thought this should work; I'm saving the wb and trying to get the Excel Application object by using wb.Application. It actually works but XLApp.Intersect fails with "Type Mismatch" error.

Dim wb As Object

Sub First()
    Dim XLApp As Object
    XLApp = CreateObject("Excel.Application")
    wb = myXL.XLApp.Workbooks.Add()
End Sub

Sub Second()
    Dim XLApp as object = wb.Application
    Dim rg as object = XLApp.Intersect(ws.UsedRange, ws.Columns("B"))
End Sub

Is it possible to get Excel Application from the workbook and still use the Intersect method?

I also tried saving the XLapp to a global variable and re-using it, but that didn't work either; same error.

I am trying to avoid using an Excel Interop reference to maintain backward compatibility with old versions of Excel.

MSDN Library _Application.Intersect Method

I noticed that my application object is of type: Microsoft.Office.Interop.Excel.ApplicationClass

Answer 1

The varocarbas answer got me to thinking about the various types I was using. So I experimented with various combinations of objects Dim ObjRange1 As Object and declared types Dim rg1 As Excel.Range

Here is the code that I tested and it works fine except the one at the end which gave me the "Type Mismatch" error.

Sub testXL1()

    Dim XLApp As Object
    Dim wb As Object
    Dim ws As Object

    XLApp = CreateObject("Excel.Application")
    XLApp.visible = True
    wb = XLApp.Workbooks.Add()
    XLApp = wb.application
    ws = wb.worksheets(1)
    ws.cells(1, 1) = "First"
    ws.cells(2, 2) = "hello"

    'this works fine
    Dim rg1 As Microsoft.Office.Interop.Excel.Range
    Dim rg2 As Microsoft.Office.Interop.Excel.Range
    Dim rg3 As Microsoft.Office.Interop.Excel.Range
    rg1 = ws.usedRange
    rg2 = ws.columns("B")
    rg3 = XLApp.Intersect(rg1, rg2)
    rg3.Select()

    'this works fine
    Dim rg4 As Object
    rg4 = XLApp.Intersect(rg1, rg2) 'Public member 'Intersect' on type 'Object()' not found.
    rg4.Select()

    'this works fine
    Dim ObjRange1 As Object = ws.usedRange
    Dim ObjRange2 As Object = ws.columns("B")
    Dim rg5 As Microsoft.Office.Interop.Excel.Range
    rg5 = XLApp.Intersect(ObjRange1, ObjRange2)
    rg5.Select()

    'this works fine
    Dim ObjRange3 As Object
    ObjRange3 = XLApp.Intersect(ObjRange1, ObjRange2)
    ObjRange3.Select()

    'this give a Type Mismatch error
    ObjRange3 = XLApp.Intersect(ws.usedRange, ws.columns("B"))
    ObjRange3.Select()


End Sub

So I guess the answer is to set the ranges to object variables before using them as parameters in ObjRange3 = XLApp.Intersect(ObjRange1, ObjRange2)

varocarbas answer had to do with using DirectCast

rg = DirectCast(XLApp, Microsoft.Office.Interop.Excel.Application).Intersect(...

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