add, update and delete database data from code behind using asp.net C#

my connection string is:

<connectionStrings>
<add name="NorthwindConnectionString" 
connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\SecurityTutorials.mdf;Integrated Security=True;User Instance=True" 
providerName="System.Data.SqlClient"/>
</connectionStrings>

and by using the below line i'll connect to the database from code behind:

connection = new SqlConnection(ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString)

currently i'm using below code at my .aspx page to add, update and delete the data from database.

<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
        ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" 
        SelectCommand="SELECT [ProductID], [ProductName], [Discontinued] FROM [Alphabetical list of products]"
        InsertCommand = "INSERT INTO [Alphabetical list of products] (ProductID, ProductName, Discontinued)VALUES(@ProductID,@ProductName,@Discontinued)"
        UpdateCommand = "UPDATE [Alphabetical list of products] SET [ProductName] = @ProductName WHERE [ProductID] = @ProductID"
        DeleteCommand = "DELETE FROM [Alphabetical list of products] WHERE [ProductID]=@ProductID">
        <InsertParameters>
            <asp:Parameter Name="ProductID" Type="String" />
            <asp:Parameter Name="ProductName" Type="String" />
            <asp:Parameter Name="Discontinued" Type="String" />
        </InsertParameters>           
        <UpdateParameters>
            <asp:Parameter Name="ProductName" Type="String" />             
            <asp:Parameter Name="ProductID" Type="Int32" />
        </UpdateParameters>
        <DeleteParameters>
            <asp:Parameter Name="ProductID" Type="Int32" />
        </DeleteParameters>
    </asp:SqlDataSource>

i'm using ListView and by the below code i could access to all and edit all the data of the database from code behind:

 using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString))
    {
        var selectCommand = new SqlCommand("SELECT [ProductID], [ProductName], [Discontinued] FROM [Alphabetical list of products]");
        var dataAdapter = new SqlDataAdapter();
        var dataSet = new DataSet();
        selectCommand.CommandType = CommandType.Text;
        selectCommand.Connection = connection;
        dataAdapter.SelectCommand = selectCommand;

        connection.Open();
        dataAdapter.Fill(dataSet, "myDataSet");
        connection.Close();
        foreach (DataRow dr in dataSet.Tables["myDataSet"].Rows)
        {
            dr["ProductID"] = dr["ProductID"]+"00";
        }   

        ListView1.DataSource = dataSet;
        ListView1.DataBind();
    }

my question is how can i do the add, edit, update and delete from the code behind and delete the from the .aspx page. because i'm developing a template and i want to do every thing from code behind.
appreciate your consideration.