Simple web control isn't rendering properly

I've got a simple web control, which works, sort of. It's just not allowing (no errors though) any variable in the control to be set, whatever I try, it's just not displaying anything apart from default values.

My control:

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="Message.ascx.cs" Inherits="Message" %>

<asp:Panel runat="server" ID="ErrorPanel">

    <asp:Literal
        runat="server"
        ID="MessageTextLit"    
    />

</as开发者_StackOverflow中文版p:Panel>

/// <summary>
/// The type of the message, good, bad etc.
/// </summary>
public enum MessageType
{
    Good,
    Error
}

public partial class Message : System.Web.UI.UserControl
{
    public string MessageText { get; set; }         // Text of the error message
    public MessageType Type { get; set; }           // Message type

    protected void Page_Load(object sender, EventArgs e)
    {
        MessageTextLit.Text = MessageText;

        // Set correct CSS class
        if (Type == MessageType.Good)
            ErrorPanel.CssClass = "good-box";
        else if (Type == MessageType.Error)
            ErrorPanel.CssClass = "bad-box";

    }
}

On my page I have it as:

<CrystalControls:Message runat="server" ID="TopMessage" Visible="false" />

Then when a button is pressed I do:

if (QuestionSubject.Length < 5)
{
    TopMessage.MessageText = "Soemthing message";
    TopMessage.Type = MessageType.Error;
    TopMessage.Visible = true;
}
else if (QuestionBody.Length < 10)
{
    TopMessage.MessageText = "Error message";
    TopMessage.Type = MessageType.Error;
    TopMessage.Visible = true;
}

I've checked, and the if's are firing, it's not throwing any errors, but none of the variables in the Message class are ever setting! They just default whatever I do. I can't see to change any of their values.

Page_Load is too early to be doing this.

We generally would do this type of thing in OnPreRender, that way if any of your properties get changed during the life-cycle you will pick up the correct values.

protected override void OnPreRender(EventArgs e)
{         
  MessageTextLit.Text = MessageText;          // Set correct CSS class         
  if (Type == MessageType.Good)              
      ErrorPanel.CssClass = "good-box";         
  else if (Type == MessageType.Error)             
      ErrorPanel.CssClass = "bad-box";      
}