**Summary of the problem**

How to read the output value of a formula in a cell, using .NET and Openxml.

**Goal**

Using .NET open-xml, to read a value of a cell that contains a formula and that is **not** calculated at compile-time, but at run time.

For example if we have a cell with the formula: =SUM(O32:O80). I need to read the output value after evaluating this formula, using .NET.

In my case the formulas is getting calculated only when you open the excel file and press enable editing button, only then, the formulas get calculated.

So in other words, is there a way to force calculating the formulas of the cells to then read the output cell values from .NET.

**Not relevant answers**

As the value of the formula is not getting calculated at compile-time, I would say a not relevant answer would be in the form of:

- Getting the Cell using (SpreadsheetDocument spreadSheet = SpreadsheetDocument.Open(tmpTempletePath, true)){

...

Cell cell = row.Elements<Cell>().Where(c => c.CellReference.Value == cellReference).FirstOrDefault();
- Getting the cellValue using the normal way or getting it as a SharedString for example as follows: string value = workbookPart.SharedStringTablePart.SharedStringTable.Elements<SharedStringItem>().ElementAt(Convert.ToInt32(cell.CellValue.Text)).InnerText;
- Force calculation by setting calculation properties

I tried:

```
Report.Workbook.CalculationProperties.CalculationOnSave = true;
Report.Workbook.CalculationProperties.ForceFullCalculation = true;
Report.Workbook.CalculationProperties.FullCalculationOnLoad = true;
```

**Why the answers above are not relevant**

Because those answers give the value of the cell, but not the calculated output value of the formula included in the cell. In my case, the excel document that I'm working on is a very complex price calculation document with more than 70 defined names that point to ranges and cells, and a large number of formulas that include these defined names in their calculations to calculate a total price value. Meaning that to make the calculation in C# based on the data I have, is a big project compared with just reading the value after it gets calculated by excel at run-time.

**Idea**

I got an idea to include a visual-basic based button in a sheet that will read the value after calculation and persist it to a file that I read from .NET? Any ideas?

Many thanks in advance

Best Regards