EPPlus - Unable to get values of NPV and IRR functions from excel - asp.net

Question

I have a model in excel and trying to feed inputs through ASP.NET to the excel and returning the back the model results over the grid in the front end. I'm using EPPlus package in ASP.NET as it doesn't need MS Office to be installed.
I have trouble getting the value of the cell where NPV [Net Present Value] and IRR [Internal rate of return] functions have been used. It always returns #VALUE or #NAME. As a workaround, I was able to calculate NPV manually but I'm having a tough time with IRR.
Is there a way in EPPlus to paste all the cells as values in the worksheet?
Or is there any other alternative?
Please help and thanks in advance
Update : I have EPPlus 4.5.3.1 and Visual studio 2013.
string strfilepath = Server.MapPath(destPath);
FileInfo fileInfo = new FileInfo(strfilepath);
ExcelPackage p = new ExcelPackage(fileInfo);
ExcelWorksheet myWorksheet = p.Workbook.Worksheets["Financial"];
GridView1.Rows[0].Cells[2].Text = float.Parse(myWorksheet1.Cells["f57"].Value.ToString()).ToString("N2");

Answer 1

I have tried all possible ways in EPPlus but I was not able to calculate IRR. I came up with a solution in SQL and it gives the result close to excel 's IRR function.
CREATE FUNCTION [dbo].[Ufn_irr1] (#strIDs1 VARCHAR(10),
#strIDs2 VARCHAR(10),
#guess DECIMAL(30, 10))
returns DECIMAL(30, 10)
AS
BEGIN
DECLARE #t_IDs TABLE
( a
id INT IDENTITY(0, 1),
value DECIMAL(30, 10)
)
DECLARE #strIDs VARCHAR(max)
SET #strIDs = #strIDs1 + ',' + #strIDs2
DECLARE #strID VARCHAR(12),
#sepPos INT,
#NPV DECIMAL(30, 10)
SET #strIDs = COALESCE(#strIDs + ',', '')
SET #sepPos = Charindex(',', #strIDs)
WHILE #sepPos > 0
BEGIN
SET #strID = LEFT(#strIDs, #sepPos - 1)
INSERT INTO #t_IDs
(value)
SELECT ( Cast(#strID AS DECIMAL(20, 10)) )
WHERE Isnumeric(#strID) = 1
SET #strIDs = RIGHT(#strIDs, Datalength(#strIDs) - #sepPos)
SET #sepPos = Charindex(',', #strIDs)
END
SET #guess = CASE
WHEN Isnull(#guess, 0) <= 0 THEN 0.00001
ELSE #guess
END
SELECT #NPV = Sum(value / Power(1 + #guess, id))
FROM #t_IDs
WHILE #NPV > 0
BEGIN
SET #guess = #guess + 0.00001
SELECT #NPV = Sum(value / Power(1 + #guess, id))
FROM #t_IDs
END
RETURN #guess
END