Control not rendering if added during aspx page load call

[crabpot8]

I am working on a message system that will let out programmers easily output a message to any user. It works fine, unless the message is requested inside of a page_load on an aspx page. Then, it does not render at all.



The code does step through, and the control is added - I believe it might be being added to late in the page lifecycle to get rendered. I can't seem to find any way to tell .NET to render that control, however.



Here is my code for my master page, where most of the "meat" is located

 
1 using System;
2 using System.Collections;
3 using System.Configuration;
4 using System.ComponentModel;
5 using System.Data;
6 using System.Data.Odbc;
7 using System.Diagnostics;
8 using System.ServiceProcess;
9 using System.Drawing;
10 using System.Web;
11 using System.Web.SessionState;
12 using System.Web.UI;
13 using System.Web.UI.WebControls;
14 using System.Web.UI.HtmlControls;
15 using System.Text.RegularExpressions;
16 
17 namespace CUTS
18 {
19 public partial class BMW_Master : System.Web.UI.MasterPage
20 {
21 private void Page_Load(object sender, System.EventArgs e)
22 {
23 if (IsPostBack)
24 {
25 reCreateMessages();
26 return;
27 }
28 
29 // If we are on a new page, clear any old
30 // messages
31 ClearAllMessages();
32 }
33 private void reCreateMessages()
34 {
35 if (ViewState["messages"] == null ||
36 ViewState["messages"].ToString() == "" ||
37 ViewState["messages"].ToString() == String.Empty)
38 return;
39 
40 // Create the regex
41 string messages = (string)ViewState["messages"];
42 Regex reg = new Regex(@"~(?<message>.+?)\*(?<severity>.+?);");
43 Match m = reg.Match(messages);
44 
45 // extract the variables
46 while (m.Success)
47 {
48 string message = m.Groups["message"].ToString(),
49 severity = m.Groups["severity"].ToString();
50 
51 MessageSeverity _severity = MessageSeverity.Error;
52 
53 if (severity == "Information")
54 _severity = MessageSeverity.Information;
55 else if (severity == "Error")
56 _severity = MessageSeverity.Error;
57 else if (severity == "Success")
58 _severity = MessageSeverity.Success;
59 
60 new_message_.Controls.Add(new BMW_Message(message, _severity));
61 
62 m = m.NextMatch();
63 }
64 
65 }
66 
67 public void ClearAllMessages()
68 {
69 new_message_.Controls.Clear();
70 }
71 
72 public void AddNewMessage(string _message)
73 {
74 AddNewMessage (_message,MessageSeverity.Error);
75 }
76 
77 public void AddNewMessage(string _message, MessageSeverity _severity)
78 {
79 // Remove used special characters
80 _message = _message.Replace("~", "~");
81 _message = _message.Replace("*", "*");
82 _message = _message.Replace(";", ";");
83 
84 BMW_Message m = new BMW_Message(_message, _severity);
85 new_message_.Controls.Add(m);
86 
87 ViewState["messages"] += "~" + _message + "*" + _severity.ToString() + ";";
88 Page_Load(this, new EventArgs());
89 }
90 
91 public void Clear_All_Click(object sender, EventArgs e)
92 {
93 ViewState["messages"] = null;
94 new_message_.Controls.Clear();
95 }
96 
97 public void Clear_Me_Click(object sender, EventArgs e)
98 {
99 Button b = (Button)sender;
100 BMW_Message message = (BMW_Message)b.Parent;
101 string vs_string = message.ViewStateString;
102 
103 string vs = ViewState["messages"].ToString();
104 vs = vs.Replace(vs_string, "");
105 
106 ViewState["messages"] = vs;
107 if (vs == "")
108 ViewState["messages"] = null;
109 
110 new_message_.Controls.Remove(message);
111 }
112 }
113 }
114 public enum MessageSeverity
115 {
116 Error, Information, Success
117 }
118 
119 public class BMW_Message : CompositeControl
120 {
121 private string _message;
122 private MessageSeverity _severity;
123 
124 public BMW_Message(string message, MessageSeverity severity)
125 {
126 this._message = message;
127 this._severity = severity;
128 }
129 
130 public string ViewStateString
131 {
132 get
133 {
134 return "~" +
135 _message + "*" +
136 _severity.ToString() + ";";
137 }
138 }
139 
140 protected override void CreateChildControls()
141 {
142 Controls.Clear();
143 CreateControlHierarchy();
144 ClearChildViewState();
145 }
146 protected virtual void CreateControlHierarchy()
147 {
148 string div_style = String.Empty;
149 Color button_BackColors = Color.Transparent;
150 
151 if (_severity == MessageSeverity.Information)
152 {
153 div_style = "border: solid 3px gold; background-color: yellow; padding-left: 10px;";
154 button_BackColors = Color.Yellow;
155 }
156 else if (_severity == MessageSeverity.Success)
157 {
158 div_style = "border: solid 3px dark green; background-color: green; padding-left: 10px;";
159 button_BackColors = Color.Green;
160 }
161 else // Default to Error
162 {
163 div_style = "border: solid 3px dark red; background-color: red; padding-left: 10px;";
164 button_BackColors = Color.Red;
165 }
166 
167 // Panel Containing this, Then Form, Then to the BMW_Master
168 CUTS.BMW_Master m = (CUTS.BMW_Master)Parent.Parent.Parent;
169 
170 LiteralControl div_start = new LiteralControl("&lt;div style='" + div_style + "'>");
171 
172 Button Clear_Me = new Button();
173 Clear_Me.Text = " X ";
174 Clear_Me.BackColor = button_BackColors;
175 Clear_Me.Style.Add("float", "left");
176 Clear_Me.Style.Add("position", "relative");
177 Clear_Me.Style.Add("left", "-19px");
178 Clear_Me.Style.Add("top", "-10px");
179 Clear_Me.Click += new EventHandler(m.Clear_Me_Click);
180 
181 Button Clear_All = new Button();
182 Clear_All.Text = "Clear All";
183 Clear_All.BackColor = button_BackColors;
184 Clear_All.Style.Add("position", "relative");
185 Clear_All.Style.Add("left", "-19px");
186 Clear_All.Style.Add("top", "-10px");
187 Clear_All.Click += new EventHandler(m.Clear_All_Click);
188 
189 
190 
191 Label Message = new Label();
192 Message.Text = _message;
193 
194 LiteralControl div_end = new LiteralControl("&lt;/div>");
195 
196 this.Controls.Add(div_start);
197 this.Controls.Add(Clear_Me);
198 this.Controls.Add(Clear_All);
199 this.Controls.Add(Message);
200 this.Controls.Add(div_end);
201 }
202 }
203

I would really appreciate ANY help here - this all works absolutely if the ASPX page loads, and then someone causes a postback that creates a message. However, if the message is added in the ASPX page_load call, then the item simply does not render.



Thanks in advance,

crab

[DrBunchman]

Hi crab,

Line 23 above

 if (IsPostBack)

is testing that the page load is a PostBack before running the reCreateMessage s() sub. Remove this test and it should run when your page loads first time.

Hope this helps,

Dr B

PS Please remember to use [CODE] tags in your post by using the # button at the top of the edit window - it makes your posts much easier for everyone to read. Thanks.

[Frinavale]

I noticed that in your Page_Load line 26, you have a return.
Try removing this....