How to retrieve cell Values in Excel Sheet

    xlApp = new Microsoft.Office.Interop.Excel.Application();
    xlWorkBook = xlApp.Workbooks.Open(path, 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
    xlWorkSheet = (Microsoft.Office.Interop.Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);
    range = xlWorkSheet.UsedRange;
    for (rCnt = 1; rCnt <= range.Rows.Count; rCnt++)
        {
            for (cCnt = 2; cCnt <= range.Columns.Count; cCnt++)
            {
                if (Convert.ToString((range.Cells[rCnt, cCnt] as Microsoft.Office.Interop.Excel.Range).Value2) == productId) //condition to ge only those fields
                {
                    Microsoft.Office.Interop.Excel.Range rng = (Microsoft.Office.Interop.Excel.Range)xlWorkSheet.get_Range(xlWorkSheet.Cells[rCnt - 1, 2], xlWorkSheet.Cells[rCnt, cCnt]);      // getting those range cells                                                                                                                             
                    foreach (Range c in rng.Cells)
                    {
                        string changedCell = c.get_Address(Type.Missing, Type.Missing, XlReferenceStyle.xlA1, Type.Missing, Type.Missing);                           
                        if (Convert.ToString(c.Value2) == "SomeValue")
                        {
                        }
                    }
                }

I have an excel sheet where I'm retrieving a range of cells based on a condition,now in the if condition equals the somevalue and say the cell is B3, I want to get the value of B4 in that if condition,how can I do it