问题
Him
I am using a ASP.NET/VB.NET with SQL-Server-2012.
I have a a GridView column with 3 fields and 1 template field as shown below:
<asp:GridView ID="grdItems" runat="server" AutoGenerateColumns="False" CellPadding="4" DataSourceID="SqlDataSource3" Font-Names="Tahoma" ForeColor="#333333" GridLines="None">
<AlternatingRowStyle BackColor="White" ForeColor="#284775" />
<Columns>
<asp:BoundField DataField="item_name" HeaderText="Item" SortExpression="item_name" />
<asp:BoundField DataField="item_cost" HeaderText="Cost (inc. VAT)" SortExpression="item_cost" />
<asp:BoundField DataField="item_quantity" HeaderText="Quantity" SortExpression="item_quantity" />
<asp:TemplateField HeaderText="Sub-Total (inc. VAT)">
<ItemTemplate>
<asp:Label ID="TextBox3" runat="server" Text='<%# Convert.ToInt32(Eval("item_quantity")) * Convert.ToDouble(Eval("item_cost"))%>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<FooterTemplate>
<asp:Label ID="lblTotalPrice" runat="server" />
</FooterTemplate>
</asp:TemplateField>
</Columns>
<EditRowStyle BackColor="#999999" />
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" HorizontalAlign="Center" VerticalAlign="Middle" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" HorizontalAlign="Center" VerticalAlign="Middle" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<SortedAscendingCellStyle BackColor="#E9E7E2" />
<SortedAscendingHeaderStyle BackColor="#506C8C" />
<SortedDescendingCellStyle BackColor="#FFFDF8" />
<SortedDescendingHeaderStyle BackColor="#6F8DAE" />
</asp:GridView>
Code behind:
Imports System.Data.SqlClient
Imports System.Data
Partial Class ProjectReport
Inherits System.Web.UI.Page
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
Dim ProjectID = Session("project_id")
Session("ProjectID") = ProjectID
End Sub
Protected Sub grdItems_RowDataBound(sender As Object, e As GridViewRowEventArgs)
Dim totalPrice As Decimal = 0
If e.Row.RowType = DataControlRowType.DataRow Then
Dim lblPrice As Label = DirectCast(e.Row.FindControl("lblTotalPrice"), Label)
Dim price As Decimal = [Decimal].Parse(lblPrice.Text)
totalPrice += price
End If
If e.Row.RowType = DataControlRowType.Footer Then
Dim lblTotalPrice As Label = DirectCast(e.Row.FindControl("lblTotalPrice"), Label)
lblTotalPrice.Text = totalPrice.ToString()
End If
End Sub
End Class
DataBound()
Private Sub BindData()
Dim conn As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
Dim query As New SqlCommand("SELECT Items.item_name, Items.item_cost, project_items.item_quantity FROM Items INNER JOIN project_items ON items.item_id = project_items.item_id WHERE project_items.project_id = @parameter", conn)
query.Parameters.AddWithValue("@UserID", Session("ProjectID"))
Dim da As New SqlDataAdapter(query, conn)
da.SelectCommand = query
Dim table As New DataTable()
da.Fill(table)
grdItems.DataSource = table
grdItems.DataBind()
End Sub
The last column (the template field) multiplies the quantity field with the cost field.
How do I calculate all the values (by adding) in the template field?
回答1:
You must use the databinding events to sum the values. See this example and adapt to your needs:
private Decimal OrderTotal;
protected void GridView1_DataBinding(object sender, EventArgs e)
{
OrderTotal = 0.0M;
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
//Keep adding the subtotal here
OrderTotal += Subtotal;
}
}
protected void GridView1_DataBound(object sender, EventArgs e)
{
//Set a control with the total sum
LabelOrderTotal.Text = OrderTotal.ToString("C");
}
Basically you keep adding the values in the RowDataBound event and in the DataBound event you set a label with the total sum. Alternatively, you can iterate over your grid in the DataBound event and add everything up.
回答2:
I personally would do it by performing the addition (as well as the multiplication actually) in the RowDataBound event...
回答3:
Iterate through all DataRow rows on the DataBound event of the gridview and add the value of TextBox3 to a running total variable.
Protected Sub grdItems_DataBound(ByVal sender as Object, ByVal e as EventArgs)
Dim row As GridViewRow = Nothing
Dim runningTotal As Double = 0.0
For i As Integer = 0 to grdItems.Rows.Count
row = grdItems.Rows(i)
If row.RowType = DataControlRowType.DataRow Then
' Add error handling here
runningTotal += Ctype(CType(row.FindControl("TextBox3"), Label).Text, Double)
End If
Next i
End Sub
回答4:
You can try this...
decimal totalScore=0;
protected void gd__RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
Label TextBox3= (Label)e.Row.FindControl("TextBox3");
decimal points = Decimal.Parse(TextBox3.Text);
totalScore += points;
}
if (e.Row.RowType == DataControlRowType.Footer)
{
Label lblTotal = (Label)e.Row.FindControl("lblTotal");
lblTotal.Text = totalScore.ToString();
}
}
回答5:
<asp:TemplateField HeaderText="first_name" SortExpression="first_name">
<EditItemTemplate>
<asp:TextBox ID="TextBox_first_name" runat="server" Text='<%# Bind("first_name") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label_first_name" runat="server" Text='<%# Bind("first_name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="middle_name" SortExpression="middle_name">
<EditItemTemplate>
<asp:TextBox ID="TextBox_middle_name" runat="server" Text='<%# Bind("middle_name") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label_middle_name" runat="server" Text='<%# Bind("middle_name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="last_name" SortExpression="last_name">
<EditItemTemplate>
<asp:TextBox ID="TextBox_last_name" runat="server" Text='<%# Bind("last_name") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label_last_name" runat="server" Text='<%# Bind("last_name") %>'></asp:Label>
</ItemTemplate>
Protected Sub GridView_clients_RowCommand(sender As Object, e As GridViewCommandEventArgs) Handles GridView_clients.RowCommand
If e.CommandName = "Select" Then
Dim index As Integer = Convert.ToInt32(e.CommandArgument) 'gets the row
'........................................
Dim client_first_name As String = DirectCast(GridView_clients.Rows(index).FindControl("Label_first_name"), Label).Text.ToString
Dim client_middle_name As String = DirectCast(GridView_clients.Rows(index).FindControl("Label_middle_name"), Label).Text.ToString
Dim client_last_name As String = DirectCast(GridView_clients.Rows(index).FindControl("Label_last_name"), Label).Text.ToString
'MsgBox(client_first_name)
'MsgBox(client_middle_name)
'MsgBox(client_last_name)
lb_test.Text = client_first_name & " " & client_middle_name & " " & client_last_name
End If
End Sub
from Craig Lewis Johnson from FSSA - Indiana
来源：https://stackoverflow.com/questions/16038234/getting-total-values-of-a-certain-column-from-gridview