Question

I use Access 2007, SQL Server 2005 and 2008, and C#.net with VS20010.

I need to validate, then import an Excel workbook that has been posted to a SP document library. I wrote the program using VBA in A2k7 so I could get it working, get all my thoughts together, etc. Shortly, I’m going to start converting it to C# so I can run it on a scheduled basis from my SQL Server agent. Authentication may be fun, we’ll see.

In my Access VBA program, I use a simple statement to create a multi-dimensional array of “variants”. This allows me to test every single cell for the correct type before I try to assign it to a local variable. Certain cells must be numeric. Others, I use as strings, even if they’re numeric. Since the data may be hand-entered, I could see virtually any content in the cells…one of the reasons I don’t just import it, since most import vehicles (ACCESS, SSIS) use Excel’s determination as to the column’s “type”.

    '
'   Get the range of used cells from the worksheet and stuff it into an array
'
xlApp.visible = False                   'Don't let the workbook be shown
Set xlWB = xlApp.Workbooks.Open(URL)    'Open the workbook
Set xlSH = xlWB.Worksheets(1)           'Must be the first worksheet in the workbook
HandleMessages 1, 0, 1, "Working on Workbook " & xlWB.NAME & ", Worksheet " & xlSH.NAME
Set xlRA = xlSH.UsedRange               'xlRA is the range of cells in the first workbook that are "USED"
strSheetArray = xlRA                    'This sets an array of variants to the two dimensional range xlRA

So, going to C#, what do I do about the lack of a non-typed “variant”? How do I proceed? Anyone done it?

Answer 1

You can use dynamic in C# 4.0.

http://msdn.microsoft.com/en-us/library/dd264736.aspx

The type is a static type, but an object of type dynamic bypasses
static type checking. In most cases, it functions like it has type
object. At compile time, an element that is typed as dynamic is
assumed to support any operation. Therefore, you do not have to be
concerned about whether the object gets its value from a COM API, from
a dynamic language such as IronPython, from the HTML Document Object
Model (DOM), from reflection, or from somewhere else in the program.
However, if the code is not valid, errors are caught at run time.

The link shows examples of using dynamic with Excel.