How to bind one column to gridview which is not present in database

How to bind one column to the gridview which is not present in the database?

I want to display the total unit in the last column named Total Unit but it is not present in database.

I got an argument exception:

开发者_开发百科

Column 'tunit' does not belong to table.

foreach(DataRow row in dt.Rows )
{
   object[] obj=new object[2];
   obj[0] = row["Transaction_Id"];
   obj[1] = row["tunit"];
   dtgrid.Rows.Add(obj);
}

---

The best solution to this problem is to implement unbound column as it is explained in the Unbound Columns topic.

---

if you are binding a list, you can add a property to that list and bind to the grid using eval("PropertyName")

---

When you prepare the select query make sure you have one more extra column with the total value you want for that particular row, then you can specify a column in the gridview as follows, make sure you specify

'AutoGenerateColumns = false;

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="sds_datasourceName">  
<Columns>   
            <asp:TemplateField HeaderText="Total" >
                <itemtemplate>
                    <asp:Label ID="Total" runat="server" Text='<%# Bind("Total") %>'></asp:Label>
                </itemtemplate>

            </asp:TemplateField>
</Columns>
        </asp:GridView>