Need to display total price in gridview - asp.net

Question

just been trying to display my total price from a column in my footer row.
here is my code to try that but it doesnt seem to be even going through it when i put a break point in
Sub gvPayments_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
' add the UnitPrice and QuantityTotal to the running total variables
invoiceTotal += Convert.ToDecimal(DataBinder.Eval(e.Row.DataItem, "Total"))
ElseIf e.Row.RowType = DataControlRowType.Footer Then
e.Row.Cells(0).Text = "Total:"
' for the Footer, display the running totals
e.Row.Cells(5).Text = invoiceTotal.ToString("c")
e.Row.Cells(5).HorizontalAlign = HorizontalAlign.Right
e.Row.Font.Bold = True
End If
End Sub
If you need any more of my code, just ask!

Answer 1

I like to use a method that doesn't require handling any events. It just uses a TemplateField and a couple different functions. In your GridView, make the column like this:
<asp:TemplateField HeaderText="Total">
<ItemTemplate><%#DisplayAndAddToTotal(Eval("Total").ToString(), "Total")%></ItemTemplate>
<FooterTemplate><%#GetTotal("Total")%></FooterTemplate>
</asp:TemplateField>
The second parameter to DisplayAndAddToTotal can be any string you want as long as you use the same string in GetTotal. I usually just use the field name again though. Here are the two functions used, DisplayAndAddToTotal and GetTotal. They use a Hashtable to store the totals so that it works with any number of columns you want to add up. And they also work with counting the number of "True"s for a Boolean field.
Protected total As Hashtable = New Hashtable()
Protected Function DisplayAndAddToTotal(itemStr As String, type As String) As Double
Dim item As Double
If itemStr = "True" Then
item = 1
ElseIf Not Double.TryParse(itemStr, item) Then
item = 0
End If
If total.ContainsKey(type) Then
total(type) = Double.Parse(total(type).ToString()) + item
Else
total(type) = item
End If
Return item
End Function
Protected Function GetTotal(type As String) As Double
Try
Dim result As Double = Double.Parse(total(type).ToString())
Return result
Catch
Return 0
End Try
End Function