You could manipulate the workbook's VBA project with code.  To do this you
need to reference the VBA Extensibility library (in the VBA Editor for your
workbook, go to Tools > References and check "Visual Basic Extensibility
Library").  

Then you could use code like this to append the code from one module to
another:

    Dim oBook As Workbook
    Dim oModule1 As VBComponent, oModule2 As VBComponent

    Set oBook = Workbooks.Open("c:\book1.xls")
    Set oModule1 = oBook.VBProject.VBComponents("Module1")
    Set oModule2 = oBook.VBProject.VBComponents("Sheet1")

    'Get the code in Module1
    Dim n As Long, sCode As String
    n = oModule1.CodeModule.CountOfLines
    sCode = oModule1.CodeModule.Lines(1, n)

    'Append the code from Module1 to the code module for Sheet1
    n = oModule2.CodeModule.CountOfLines
    'oModule2.CodeModule.DeleteLines 1, n 'Use if you want to clear the
code in Sheet1 first
    oModule2.CodeModule.InsertLines n + 1, sCode

Hope this helps,

Lori Turner
Microsoft Developer Support

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