creating excel charts with dynamic data range in vb.net - excel

Question

I am creating an Excel pie and bar charts from exported data pragmatically. Here I need to pick the cell range dynamically. For example, after header name all data should be picked up until cell contains "TOTAL" line.
Below is my current code.
If String.IsNullOrEmpty(HttpContext.Current.Request.QueryString("oversight")) Then 'This is Summary Level
Dim worksheet2 As ExcelWorksheet = pkg.Workbook.Worksheets.Add("Chart - CY Consumable")
worksheet2.DefaultColWidth = 15
Dim consumableChart As OfficeOpenXml.Drawing.Chart.ExcelPieChart = worksheet2.Drawings.AddChart("ConsumableChart", OfficeOpenXml.Drawing.Chart.eChartType.Pie)
Dim r1, r2 As ExcelRange
r1 = worksheet.Cells("A6:A12") // here I want it to be selected dynamically after header and before the total line
r2 = worksheet.Cells("B6:B12")
consumableChart.Series.Add(r2, r1)
consumableChart.Style = OfficeOpenXml.Drawing.Chart.eChartStyle.Style2
consumableChart.Title.Text = "FY 2018 Consumable by Regional & Central Oversight Programs"
consumableChart.Legend.Remove()
consumableChart.SetPosition(1, 1, 1, 1)
consumableChart.SetSize(1040, 880)
consumableChart.DataLabel.ShowLeaderLines = True
consumableChart.DataLabel.ShowCategory = True
consumableChart.DataLabel.ShowPercent = True
Thanks in advance.

Answer 1

Dim totalRow As Integer
If ds.Tables.Count > 0 Then
Dim k As Integer = 0
For j As Integer = 0 To ds.Tables(0).Columns.Count - 1
If Not skip.Contains(j) Then
If columnNames.Count > 0 AndAlso columnNames.Count = (ds.Tables(0).Columns.Count - skip.Count) Then
strTitle = columnNames(k)
Else
strTitle = ds.Tables(0).Columns(j).ColumnName.Replace("_", " ")
End If
worksheet.Cells(p, k + 1).Value = strTitle
k = k + 1
End If
Next
Dim i As Integer = p + 1
For Each r As DataRow In ds.Tables(0).Rows
If includeTotals OrElse (Not r.Item(2).ToString().Trim().ToUpper().StartsWith("TOTAL") AndAlso _
Not r.Item(2).ToString().Trim().ToUpper().StartsWith("SUBTOTAL") AndAlso _
Not r.Item(2).ToString().Trim().ToUpper().StartsWith("TOTAL") AndAlso _
Not r.Item(2).ToString().Trim().ToUpper().StartsWith("SUBTOTAL")) Then
k = 0
For j As Integer = 0 To ds.Tables(0).Columns.Count - 1
If Not skip.Contains(j) Then
If r.Item(j) Is DBNull.Value Then
worksheet.Cells(i, k + 1).Value = ""
Else
If k = 0 Then
worksheet.Cells(i, k + 1).Style.Numberformat.Format = "#"
worksheet.Cells(i, k + 1).Value = r.Item(j).ToString()
Else
worksheet.Cells(i, k + 1).Value = r.Item(j)
End If
End If
// Checking if it is first col last row
If r.Item(j).ToString().Contains("TOTAL") Then
totalRow = i
End If
If r.Item(j).GetType().Name = "Decimal" Then
If roundUp Then
If useParens Then
worksheet.Cells(i, k + 1).StyleID = 2
Else
worksheet.Cells(i, k + 1).StyleID = 2 '4
End If
Else
If useParens Then
worksheet.Cells(i, k + 1).StyleID = 1
Else
worksheet.Cells(i, k + 1).StyleID = 1 '3
End If
End If
End If
k = k + 1
End If
Next
i = i + 1
End If
Next
End If
If String.IsNullOrEmpty(HttpContext.Current.Request.QueryString("oversight")) Then 'This is Summary Level
Dim worksheet2 As ExcelWorksheet = pkg.Workbook.Worksheets.Add("Chart - CY Consumable")
worksheet2.DefaultColWidth = 15
// showing the criteria
p = 1
If includeCriteria Then
Try
Dim reportTitle As String = String.Empty
reportTitle = "Central/Regional Oversight Programs"
Dim sb As StringBuilder = New StringBuilder()
sb.Append(reportTitle)
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
sb.Append("Budget Fiscal Year : ")
sb.Append(HttpContext.Current.Session("bfy"))
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
sb.Append("Currently viewing transactions from inception through ")
Dim fm As Integer = CInt(HttpContext.Current.Session("fm"))
If fm < 4 Then
sb.Append(MonthName(fm + 9))
sb.Append(" ")
sb.Append(CInt(HttpContext.Current.Session("fy")) - 1)
Else
sb.Append(MonthName(fm - 3))
sb.Append(" ")
sb.Append(HttpContext.Current.Session("fy"))
End If
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
If String.IsNullOrEmpty(HttpContext.Current.Request.QueryString("division")) Then
sb.Append("Fund Center(s) : ALL")
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
Else
sb.Append("Fund Center(s) : ")
sb.Append(HttpContext.Current.Request.QueryString("division"))
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
End If
If String.IsNullOrEmpty(HttpContext.Current.Request.QueryString("fa5")) Then
sb.Append("Func Area 5 : ALL")
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
Else
sb.Append("Func Area 5 : ")
sb.Append(HttpContext.Current.Request.QueryString("fa5"))
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
End If
If Not String.IsNullOrEmpty(HttpContext.Current.Request.QueryString("oversight")) Then
sb.Append("Oversight Program - ")
sb.Append(HttpContext.Current.Request.QueryString("oversight"))
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
End If
sb.Append("FBMS data as of ")
sb.Append(HttpContext.Current.Application("lastUpdated_BIA"))
sb.Append(" at close of business.")
worksheet2.Cells(p, 1).Value = sb.ToString()
sb.Length = 0
p = p + 1
worksheet2.Cells(p, 1).Value = ""
p = p + 1
Catch ex As Exception
For r As Integer = 1 To p - 1
worksheet2.DeleteRow(1, True)
Next
p = 1
End Try
End If
//create chart in new tab
Dim consumableChart As OfficeOpenXml.Drawing.Chart.ExcelPieChart = worksheet2.Drawings.AddChart("ConsumableChart", OfficeOpenXml.Drawing.Chart.eChartType.Pie)
Dim r1, r2 As ExcelRange
// setting the value to check the last row
Dim startColumn As String = "A"
Dim endColumn As String = "B"
Dim startIndex As Integer = 8 // Index where to start
Dim endIndex As Integer = totalRow - 1 'this is determined based on the TOTAL Line from above code
// checking and setting the values and label of pie chart
r1 = worksheet.Cells(String.Concat(startColumn, startIndex.ToString(), ":", startColumn, endIndex))
r2 = worksheet.Cells(String.Concat(endColumn, startIndex.ToString(), ":", endColumn, endIndex))
consumableChart.Series.Add(r2, r1)
consumableChart.Style = OfficeOpenXml.Drawing.Chart.eChartStyle.Style2
consumableChart.Title.Text = "FY 2018 Consumable by Regional & Central Oversight Programs"
consumableChart.Legend.Remove()
consumableChart.SetPosition(5, 5, 5, 5)
consumableChart.SetSize(1040, 880)
consumableChart.DataLabel.ShowLeaderLines = True
consumableChart.DataLabel.ShowCategory = True
consumableChart.DataLabel.ShowPercent = True