Question

I’m reading data from database and showing it in a page for editing:

    <h2>Create new topic: 
    <asp:Label ID="_lblTopicName" runat="server" Text=""></asp:Label></h2>
      <p>
      Edit Level:
      <br/>
      <asp:DropDownList ID="_dtlEditRole" runat="server"></asp:DropDownList>
      <br/>
      View Level:
      <br/>
      <asp:DropDownList ID="_dtlViewRole" runat="server"></asp:DropDownList>
      <br/>
      <asp:TextBox ID="_tbxTopicText" TextMode="MultiLine" runat="server" Height="204px" 
        Width="885px"></asp:TextBox>
    </p>
  <asp:Button ID="_btnSaveTopic" runat="server" Text="Save" onclick="_btnSaveTopic_Click" />

I fill the fields in Page_PreRender() like so:

    private string _topicString;
    private Topic _topic = null;
    private Topics_GetTopicByTopicResult _findTopicResults = null;

    protected void Page_PreRender(object sender, EventArgs e)
    {
        // Load the User Roles into checkboxes.
        _dtlEditRole.DataSource = Roles.GetAllRoles();
        _dtlEditRole.DataBind();
        _dtlViewRole.DataSource = Roles.GetAllRoles();
        _dtlViewRole.DataBind();

        _topicString = Request.QueryString["Topic"];

        if (String.IsNullOrEmpty(_topicString))
        {
            Response.Redirect("~/Default.aspx");
        }
        else
        {
            _topic = new Topic();
            _findTopicResults = _topic.FindTopic(_topicString);

            if (_topic != null)
            {
                // Check if the user has permission to access
                if (RoleHelper.IsEditAllowed(_findTopicResults.ViewRoleName))
                {
                    _lblTopicName.Text = _findTopicResults.Topic;
                    _tbxTopicText.Text = _findTopicResults.Text;

                    _dtlEditRole.SelectedValue = _findTopicResults.EditRoleName;
                    _dtlViewRole.SelectedValue = _findTopicResults.ViewRoleName;
                }
                else
                {
                    Response.Redirect("~/Error.aspx?ReturnUrl=" + HttpUtility.UrlEncode(Request.RawUrl));
                }
            }
            else
            {
                Response.Redirect("~/CreateTopic.aspx?Topic=" + _topicString);
            }
        }
    }

But now when i click _btnSaveTopic button the fields:

    private string _topicString;
    private Topic _topic = null;
    private Topics_GetTopicByTopicResult _findTopicResults = null;

They are all NULL and im not able to update aything.

Here’s my button click event:

    protected void _btnSaveTopic_Click(object sender, EventArgs e)
    {
            _topic.UpdateTopic(_findTopicResults.ID, _findTopicResults.Topic, _tbxTopicText.Text,
                               _dtlViewRole.SelectedItem.Text, _dtlEditRole.SelectedItem.Text);
            Response.Redirect("~/ViewPage.aspx?Topic=" + _topicString);
    }

What would be the right way doing this?

Answer 1

ASP.NET Page Life Cycle states that Page_Init should be used to ‘initialize control properties’ which looks like what you are doing.

Also, it’s usually good practice to breakup such large sections of code into smaller refactored methods. Try to keep the amount of code directly placed in event handlers to a minimum.

You can start by right-clicking a section of highlighted code in visual studio -> refactor -> extract method

Also, if you need more help understanding how to improve your code, you should ask a question pointing to this question on the code review site: here