(EDIT: Sorry, example solution below is written in VBA. Should be straightforward to convert to c#)
Get the value and format it using the cells number format.
Example:
Cell(1,1) has the value "2013-01-01" entered.
I apply a local number format so it looks like this:
"tisdag, januari 01, 2013"
I shrink the column so "#######" is displayed.
Run this macro:
Sub codeproject()
Dim a As Range
Set a = ActiveSheet.Cells(1, 1)
Debug.Print a.Value
Debug.Print a.Value2
Debug.Print a.Text
Debug.Print Format(a.Value, a.NumberFormat)
End Sub
Output:
2013-01-01
41275
#########
tisdag, januari 01, 2013
TL;DR
Use:
Format(a.Value, a.NumberFormat)
where a is a Range. This creates a string representation of the cells value with format applied. Does that answer your question?