C1ExcelEvaluator
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Shows how you can integrate the C1CalcEngine class with the C1Excel component.

C1Excel loads xlsx files, including cell styles and content. However, the values 
of cells that contain formulas are no re-calculated. They always return the
last value calculated by Excel. If you change the values of cells that affect
formula results, the value returned will not change.

This sample shows how you can implement an extension method for the XLCell class
that does re-calculate the cell value using the current (and possibly modified)
cell contents.

The extension method allows you to obtain updated cell values as follows:

<code>
  var sheet = _book.Sheets[0];
  var cell = sheet[0,0];
  var originalResult = cell.Value;
  var currentResult = cell.Evaluate(_book);
</code>


