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ImageButton not firing on the second time

In my ASP.Net page I need to show an HTML div who contains : Images, Text, Arrows and Connectors.
What are my "Connectors" ?
It's an ImageButton, and when the user click on this connector, the HTML div is showing a new content. This connectors are used to navigate in a TreeView.
But my problem is :
I create all my connectors (and all the HTML div content) dynamically. When the user click on the first connector the HTML div is showing new content. But on this second content, when the user click on a connector : nothing. The Click event of the ImageButton is not fired.
This is my Connector creation (on PageLoad and then on each Connector Click) :
List<Connecteur> ListConnecteur = new List<Connecteur>();
ListConnecteur = NomenclatureObj.SelectConnecteurs(DocId, ExterneData.RapidoBDDCnx);
foreach (Connecteur CeConnecteur in ListConnecteur)
{
if (CeConnecteur.FK_docversion_suivant_id != 0)
{
ImageButton ImgBtnTmp = new ImageButton();
ImgBtnTmp.Width = 30;
ImgBtnTmp.Height = 30;
ImgBtnTmp.ImageUrl = "~/images/GreenButton.png";
ImgBtnTmp.Style.Add("left", CeConnecteur.position_x_pix.ToString() + "px");
ImgBtnTmp.Style.Add("top", CeConnecteur.position_y_pix.ToString() + "px");
ImgBtnTmp.Click += new ImageClickEventHandler(ImgBtnTmp_Click);
ImgBtnTmp.CommandArgument = CeConnecteur.FK_docversion_suivant_id.ToString();
ImgBtnTmp.Style.Add("position", "absolute");
DivAffichage.Controls.Add(ImgBtnTmp);
ImgBtnTmp.CausesValidation = true;
}
}
And this is my Connector OnClick :
public void ImgBtnTmp_Click(object sender, EventArgs e)
{
ImageButton ThisBtn = sender as ImageButton;
string CommandArg = ThisBtn.CommandArgument;
int DocId = Convert.ToInt32(CommandArg);
TREEVIEW_NIVEAU++;
//DocId of the clicked connector
Session["DocId"] = DocId;
ClearDiv();
LoadDiv(DocId);
}
EDIT 1 : My whole LoadDiv() function
public void LoadDiv(int DocId)
{
#region Connecteurs
List<Connecteur> ListConnecteur = new List<Connecteur>();
ListConnecteur = NomenclatureObj.SelectConnecteurs(DocId, ExterneData.RapidoBDDCnx);
foreach (Connecteur CeConnecteur in ListConnecteur)
{
if (CeConnecteur.FK_docversion_suivant_id != 0)
{
ImageButton ImgBtnTmp = new ImageButton();
ImgBtnTmp.Width = 30;
ImgBtnTmp.Height = 30;
ImgBtnTmp.ImageUrl = "~/images/GreenButton.png";
ImgBtnTmp.Style.Add("left", CeConnecteur.position_x_pix.ToString() + "px");
ImgBtnTmp.Style.Add("top", CeConnecteur.position_y_pix.ToString() + "px");
ImgBtnTmp.Click += new ImageClickEventHandler(ImgBtnTmp_Click);
ImgBtnTmp.CommandArgument = CeConnecteur.FK_docversion_suivant_id.ToString();
ImgBtnTmp.Style.Add("position", "absolute");
DivAffichage.Controls.Add(ImgBtnTmp);
}
}
#endregion
#region Textes
List<Texte> ListTexte = new List<Texte>();
ListTexte = NomenclatureObj.SelectTextes(DocId, LANGUE_ID, ExterneData.RapidoBDDCnx);
foreach (Texte CeTexte in ListTexte)
{
Label LblText = new Label();
LblText.Text = CeTexte.contenu;
LblText.Width = CeTexte.largeur_voulue_pix;
LblText.Style.Add("left", CeTexte.position_x_pix.ToString() + "px");
LblText.Style.Add("top", CeTexte.position_y_pix.ToString() + "px");
LblText.Style.Add("position", "absolute");
DivAffichage.Controls.Add(LblText);
}
#endregion
#region Images
List<ImageNomenclature> ListImg = new List<ImageNomenclature>();
ListImg = NomenclatureObj.SelectImages(DocId, ExterneData.RapidoBDDCnx);
foreach (ImageNomenclature CetteImage in ListImg)
{
Image ImgTmp = new Image();
ImgTmp.ImageUrl = "~/Nomenclature/RAPIDO/planches/" + CetteImage.fichier_chemin;
ImgTmp.Width = CetteImage.largeur_voulue_pix;
ImgTmp.Height = CetteImage.hauteur_voulue_pix;
ImgTmp.Style.Add("left", CetteImage.position_x_pix.ToString() + "px");
ImgTmp.Style.Add("top", CetteImage.position_y_pix.ToString() + "px");
ImgTmp.Style.Add("position", "absolute");
ImgTmp.Style.Add("z-index", "-1");
DivAffichage.Controls.Add(ImgTmp);
}
#endregion
#region Flèches
List<Fleche> ListFleche = new List<Fleche>();
ListFleche = NomenclatureObj.SelectFleches(DocId, LANGUE_ID, ExterneData.RapidoBDDCnx);
foreach (Fleche CetteFleche in ListFleche)
{
string HTMLCode = "<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"800\" height=\"600\"><line x1=\"" + CetteFleche.position_x1_pix + "\" y1=\"" + CetteFleche.position_y1_pix + "\" x2=\"" + CetteFleche.position_x2_pix + "\" y2=\"" + CetteFleche.position_y2_pix + "\" stroke=\"#ff0000\"/></svg>";
//DivAffichage.InnerHtml += HTMLCode;
}
#endregion
}

You should create your dynamic control every time on Page_Init or Page_Load if you would like to handle events from them after Postback.
See links below for details:
http://msdn.microsoft.com/en-us/library/y3bwdsh3%28v=vs.140%29.aspx
http://msdn.microsoft.com/en-us/library/hbdfdyh7%28v=vs.100%29.aspx
Here you can see the same problem.
EDIT
Try to do something like this:
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
LoadDiv(Session["DocId"])
}
}

Add Ajax CalendarExtender to a dynamic textBox in ASP.NET C#

Is there a way to add Ajax CalendarExtender to a dynamic ASP.NET textbox control? Basically I'm trying to do the following:
protected void Page_Load(object sender, EventArgs e)
{
database.DB myDB = new database.DB();
DataTable myVars = new DataTable();
string myTopicID = (string)Session["myTopicID"];
bool myInvite = (bool)Session["myInvite"];
bool mySig = (bool)Session["mySig"];
string myLogo = (string)Session["myLogo"];
string myImage = (string)Session["myImage"];
string myLanguage = (string)Session["myLanguage"];
myVars = myDB.getVarFields(myTopicID, myLanguage);
AjaxControlToolkit.CalendarExtender calenderDate = new AjaxControlToolkit.CalendarExtender();
for (int i = 0; i < myVars.Rows.Count; i++)
{
Label label = new Label();
TextBox text = new TextBox();
label.Text = Convert.ToString(myVars.Rows[i]["varName"]);
myPlaceHolder.Controls.Add(label);
text.ID = Convert.ToString(myVars.Rows[i]["varName"]);
myPlaceHolder.Controls.Add(new LiteralControl(" "));
myPlaceHolder.Controls.Add(text);
if (Convert.ToString(myVars.Rows[i]["varName"]).Contains("Date:"))
{
calenderDate.TargetControlID = "ContentPlaceHolder1_" + text.ID;
myPlaceHolder.Controls.Add(calenderDate);
}
myPlaceHolder.Controls.Add(new LiteralControl("<br />"));
}
}
The error I get when I run the code above is the following:
The TargetControlID of '' is not valid. A control with ID 'ContentPlaceHolder1_Date:' could not be found.
Which makes sense I suppose since the actual text box does not exist yet. But is there a way around this?

I think ASP.NET will be smart enough to handle it if you just use text.ID, you shouldn't need to add the ContentPlaceHolder1_ prefix.
If that doesn't work, you can use the TextBox' ClientIdMode property to set it to static, then text.ID will definitely work.
The following code worked locally for me:
AjaxControlToolkit.CalendarExtender calenderDate = new AjaxControlToolkit.CalendarExtender();
for (int i = 0; i < 2; i++)
{
Label label = new Label();
TextBox text = new TextBox();
label.Text = Convert.ToString("varName");
ph1.Controls.Add(label);
text.ID = "myId" + i;
ph1.Controls.Add(new LiteralControl(" "));
ph1.Controls.Add(text);
calenderDate.TargetControlID = text.ID;
ph1.Controls.Add(calenderDate);
ph1.Controls.Add(new LiteralControl("<br />"));
}
Only differences I think you may want to investigate: I'm using latest ControlToolkit from Nuget, I'm using a ToolkitScriptManager instead of default ScriptManager. One thing that may be important to you is making sure you make text.ID unique.

Dynamic C# Not rendering on page_load

I have a method which is intended to dynamically generate a series of divs based on the entry of a value from a dropdown list. However, I wish to reuse the same code to generate the tables on the first page_load when a number already exists.
This is where the method is called. It is called GenerateTables and it is called from the Page_Load event:
if (!IsPostBack)
{
AcademicProgramme programme;
if (Request.QueryString["id"] != null)
{
programme = academic.GetAcademicProgramme(Request.QueryString["id"]);
programmeName.Text = programme.Name;
PopulateView(programme);
GenerateTables(programme.Levels);
}
}
And here is the method itself (apologies for the size of the method):
private void GenerateTables(int count)
{
for (int i = 1; i < count + 1; i++)
{
LiteralControl title = new LiteralControl();
LiteralControl close = new LiteralControl();
LiteralControl close2 = new LiteralControl();
String script = "<div class=\"ModuleProgTable\"><h3>Level " + i + "</Modules></h3></br>";
title.Text = script;
AcademicTable.Controls.Add(title);
Panel panel = new Panel();
panel.ID = "Level" + i + "Modules";
PopulatePanel(panel, GetModulesSession(i));
Button a = new Button();
a.ID = "AddModule" + i;
a.Text = "Add Module";
a.Click += (OpenPopup);
AcademicTable.Controls.Add(panel);
AcademicTable.Controls.Add(a);
close.Text = "</div> <!-- Close here -->";
close2.Text = "</div>";
AcademicTable.Controls.Add(close);
}
}
The divs are clearly being populated because if I change the dropdown option then they appear on the PostBack without fail. It's when I try to get them to render on the first page_load that I am having problems.
Any feedback and advice would be greatly appreciated!
Regards,
-Michael

get dynamically generated ajax textbox id

I have created a web application in which I need to generate textboxes depending upon the number the user enters.I have used Ajax and created textboxes dynamically but these textboxes are not accessible from code-behind.I have used find control but to no use.This is the code I use to generate textbox.
if (txtnobranches.Text != "")
{
if (Convert.ToInt32(txtnobranches.Text) != 0)
{
div_br.InnerHtml = "<table></table>";
tbl_br.Controls.Clear();
for (int i = 0; i < Convert.ToInt32(txtnobranches.Text); i++)
{
TableRow rowbr = new TableRow();
TableCell cellname = new TableCell();
cellname.Text = "Branch Location " + i.ToString();
rowbr.Cells.Add(cellname);
TableCell cellvalue = new TableCell();
cellvalue.Text = "";
TextBox txt = new TextBox();
txt.Text = "";
txt.ID = "txtbranchloc" + i.ToString();
cellvalue.Controls.Add(txt);
cellvalue.ID = "txtbranchloc" + i.ToString();
rowbr.Cells.Add(cellvalue);
tbl_br.Rows.Add(rowbr);
}
}
}

You can access the element by name using Request.Form["NameOfFormControl"] You will have to make little change in code.
In javascript
txt.Name = "txtbranchloc" + i.ToString();
In Code Behind
Note: Make sure you access it in postback otherwise you get null
if (Page.IsPostBack)
{
string firstTxtVal = Request.Form["txtbranchloc0"].ToString();
string secondTxtVal = Request.Form["txtbranchloc1"].ToString();
}
Using Request.Form Collection

Why do the rows of Table1 on post back become null?

The problem is: On postback, the table does not have the rows that were dynamically created, the rowcount is 0.
Click on the button, it should detect the checked checkboxes within the table dynamically generated.
The table is made by code when the "day" is selected using the drop down list and "the starting date" is selected using the calender.
I know there's a lot of code, but it's the least I thought I had to post, so answerers can debug. Please note I have tried hard but cannot get the solution to this.
Here’s the code:
public partial class DaySelection : System.Web.UI.Page
{
Table table1 = new Table();
Button button1 = new Button();
string the_id_checkbox;
string the_id_label;
//The need of the table ENDS
DropDownList selectdays = new DropDownList();
Label theselecteddate = new Label();
Button extract_the_selected = new Button();
Literal selected_values=new Literal();
int number_of_row = -1;
protected void Page_Load(object sender, EventArgs e)
{
CheckBox check_or_not = new CheckBox();
try
{
selected_values.Text = "";
form1.Controls.Remove(selected_values);
form1.Page.Response.Write("inside try");
for (int i = 0; i < table1.Rows.Count; i++)
{
Response.Write("inside for");
the_id_checkbox = "checkmate" + i;
the_id_label = "The_text" + i;
check_or_not = (CheckBox)table1.Rows[i].FindControl(the_id_checkbox);
if (check_or_not.Checked == true)
{
form1.Page.Response.Write("inside if");
selected_values.Text = selected_values.Text + "<br /> " + check_or_not.Checked.ToString();
selected_values.Text = selected_values.Text + " and the day is: " + ((Label)table1.Rows[i].FindControl(the_id_label)).Text;
}
else
{
Response.Write(" selection no detect");
}
}
form1.Controls.AddAt(1, selected_values);
Response.Write(selected_values.Text);
}
catch (NullReferenceException nn)
{
form1.Page.Response.Write("inside catch" + nn.Message.ToString() + nn.StackTrace);
}
extract_the_selected.Text = "Extract it";
form1.Controls.AddAt(2,extract_the_selected);
selectdays.AutoPostBack = true;
ArrayList thedays = new ArrayList();
thedays.Add("Monday" + DateTime.Now);
thedays.Add("Tuesday");
thedays.Add("Wednesday");
thedays.Add("Thursday");
thedays.Add("Friday");
thedays.Add("Saturday");
thedays.Add("Sunday");
selectdays.DataSource = thedays;
selectdays.DataBind();
form1.Controls.AddAt(3,selectdays);
Calendar1.SelectionChanged += new EventHandler(Calendar1_SelectionChanged);
}
void Calendar1_SelectionChanged(object sender, EventArgs e)
{
DateTime startdate;
string month;
month = Calendar1.SelectMonthText;
startdate = Calendar1.SelectedDate;
days_date(startdate);
}
void selectdays_SelectedIndexChanged(object sender, EventArgs e)
{
display_dates_of_day(DateTime.Parse("9-1-2010"), DateTime.Parse("9-30-2010"), selectdays.SelectedItem.Text);
}
public void days_date(DateTime startdate)
{
int noofdays;
DateTime enddate = new DateTime();
noofdays = DateTime.DaysInMonth(startdate.Year, startdate.Month) - 1;
enddate = startdate.AddDays(noofdays);
Response.Write("<br /> end date is " + enddate);
Response.Write("<br /> start date is " + startdate);
display_dates_of_day( startdate, enddate, selectdays.SelectedItem.Text);
}
void display_dates_of_day(DateTime startDate, DateTime endDate, string selectedday)
{
int Count = 0;
for (DateTime dt = startDate; dt <= endDate; dt = dt.AddDays(1.0))
{
if (dt.DayOfWeek.ToString() == selectedday)
{
table1.ID = "table1";
number_of_row = number_of_row + 1;
string date = dt.Date.ToString("dd-MMMM-yyyy");
for (int adding_rows = 0; adding_rows < 1; adding_rows++)
{
TableRow table_row1 = new TableRow();
TableCell table_cell1 = new TableCell();
TableCell table_cell2 = new TableCell();
Label The_label = new Label();
CheckBox checkmate = new CheckBox();
The_label.Text = date + " (<---date)" + number_of_row;
the_id_checkbox = "checkmate" + number_of_row;
checkmate.ID = the_id_checkbox;
the_id_label = "The_text" + number_of_row;
The_label.ID = the_id_label;
table_cell2.Controls.Add(checkmate);
table_cell1.Controls.Add(The_label);
table_row1.Controls.AddAt(0, table_cell1);
table_row1.Controls.AddAt(1, table_cell2);
table1.Rows.Add(table_row1);
}
button1.Text = "click me to export the value";
form1.Controls.Add(table1);
form1.Controls.AddAt(1, selected_values);
Count++;
}
}
Response.Write("<br /> The count of days by traversing: " + Count);
}
}

The reason you're seeing this seemingly "strange" behaviour is that you're dynamically constructing the contents of Table1 and adding it to the pages .Controls collection only in the display_dates_of_day method, which is called by:
selectdays_SelectedIndexChanged
Calendar1_SelectionChanged (indirectly)
This means that when your page is re-contructed on post-back, the controls don't exist. If you "View Source" in your browser, you'll find that after clicking the button to trigger a post-back you can't find the string "Table1" in the markup, but if you do it after clicking on a date in the calendar, you can. That's because in the "clicking the button" scenario, the control is never populated and added to the page
I'd make a few suggestions to get your head round this and solve the problem:
Start with a much simplified version of this to help you understand the asp.net page lifecycle and how it impacts on what you're doing.
Try to ensure your code adds as few controls as possible to the page dynamically as this makes things a lot simpler. i.e. Make Table1 a control that's declared in the .aspx page.