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Creating TABCONTAINER with ajax dynamically ASP.NET

Within a tabcontainer I wish to show a variety of tabs which will contain different user controls.
I need to assign the user controls to the tabs through code, and not assign the user controls as its usually done within the tags, for instance:
<ajaxToolkit:TabPanel runat="server" HeaderText="NOMBRE" ID="TabPanel1" Enabled ="true" >
<ContentTemplate>
</ContentTemplate>
</ajaxToolkit:TabPanel>
For what I need this does not work.
So here is my code to assign the tabs to the user controls, the code is as the fallowing:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Control ctrlNombre = LoadControl("~/UserCtrl/Nombre.ascx"); //user control
TabPanel1.Controls.Add(ctrlNombre); //add user control to tabpanel
}
}
And the event “onactivetabchanged” I create a menu depending on which tab is active, which will load the control, here is the code:
protected void TabContainer1_ActiveTabChanged(object sender, EventArgs e)
{
switch(TabContainer1.ActiveTabIndex)
{
case 0:
Control ctrl1 = LoadControl("~/UserCtrl/userControl1.ascx");
TabPanel1.Controls.Add(ctrlNombre);
break;
case 1:
Control ctrl2 = LoadControl("~/UserCtrl/ userControl2.ascx");
TabPanel1.Controls.Add(ctrlApPaterno);
}
}
However, this actually does work, the problem occurs when I clicked a certain button from some user control, this makes a full post back to the server as it would normally will do, but this post back causes the user control previously loaded disappear. What can I do to solve this? I really hope someone will help me out on this one, I will really appreciate it.
Here is an image of what happens when I clicked a button:
Thank you so much guys, I hope someone can help me solve this.

You may need to recreate the tab panels when the postback occurs in the Page_init because the tabpanels do not exist on post backs until they have been made...
So in Page_init you should call a function that makes the default tab collection and then later on the page you can add a new tab panel to the collection.
protected void Page_Init(object sender, EventArgs e)
{
Control ctrlNombre = LoadControl("~/UserCtrl/Nombre.ascx"); //user control
TabPanel1.Controls.Add(ctrlNombre); //add user control to tabpanel
}
Refer:
http://dorababu-meka.blogspot.com/2012/12/create-dynamical-ajax-tab-and-filling.html
http://www.c-sharpcorner.com/uploadfile/Ravish001/create-dynamic-tabs-using-ajax-tab-container-add-controls-read-them-dynamically/
Hope this makes sense.

How do I get my asp:Button to execute code in the OnClick event?

First off... I'm a noob to both ASP.net and C#. I'm updating a page that already exists to add a button..
My code..
<div style="padding: 10px;float: left;"><table><tr><td><asp:Button id="DoSomething" Text="Build Patch" runat="server" OnClick="DoSomething_click" /><br /></td></tr></table></div>
This lives in my ascx control... the code behind is...
protected void DoSomething_click(object sender, System.EventArgs e)
{
Response.Write("<script> alert('Hi');</script>");
}
It gets wired up on the default.aspx page in
<%# Register Src="~/ui/MyView.ascx" TagName="MyView" TagPrefix="UC" %>
and is used in a asp:repeater...
<UC:MyView PB=<%# Container.DataItem %> runat="server"></UC:MyView>
The repeater creates the buttons inside a <td>
I supose my question is how do I wire up the onclick for these buttons? I debug and my DoSomething_click method never hits.

Basically you need to pass your ButtonClick event from UserControl to your webpage ( that contains this userControl). This is known as Bubble up of events
User control portion:
Define your OnClick event for the Button. However, in this event you will pass this to your .aspx page.
public partial class MyView : System.Web.UI.UserControl
{
public event EventHandler SomethingButtonClick;
protected void DoSomething_Click(object sender, EventArgs e)
{
//pass the event up to the aspx page. also called bubbling up the event.
if (this.SomethingButtonClick != null)
this.SomethingButtonClick(this, e);
}
}
Your page containg the UserControl:
Set the event handler for SomethingButtonClick event in Page_Init() event as :
protected void Page_Init(object sender, EventArgs e)
{
MyView1.SomethingButtonClick += new EventHandler(MyView_SomethingButtonClick);
}
Add/Define this MyView_SomethingButtonClick in your page code behind itself.
protected void MyView_SomethingButtonClick(object sender, EventArgs e)
{
//handle the event
Response.Write("<script> alert('Hi');</script>");
}

First off, try specifying type="text/javascript" inside of your script tag:
<script type="text/javascript">alert('hi');</script>
Assuming that doesn't work:
If I understand correctly, you are trying to link the dynamically created button to the code in the codebehind. This can get very, very weird. I would recommend using a "proxy function" of sorts. Create a javascript function elsewhere on the page that gets called by the button(s)' click event. This javascript function can then initiate a postback from there. I'll see if I can find the example I've used elsewhere.
EDIT: I can't find my original example, but this is a good reference: ASP.NET postback with JavaScript
Please note that the __doPostBack() function has TWO underscores, not one.

Making an EventHandler delegate association in (!IsPostBack) doesn't work even on first page load --- why?

Works:
protected void Page_Load(object sender, EventArgs e)
{
myButton.Click += new EventHandler(myButton_Click);
}
Doesn't work:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
myButton.Click += new EventHandler(myButton_Click);
}
}
Now, what I expected in the second example was for the eventhandler to be wired to the button only when it is not a postback (i.e. the first time the page is loaded), and then on any postback, the button would no longer run the method associated with the event. That doesn't seem to be the case --- from the very first load (not a postback), the button does nothing when clicked.
My suspicion is that this is related to the page life cycle --- but I'm not quite sure where this falls into that. If I understand correctly, the method associated with the event gets run after the page has posted back (even if you clicked it on the first time the page loads), but I'm referring to the wiring up of the event to the method with the EventHandler delegate, not the actual running of the associated method.
Note: this is purely an attempt to gain a better understanding of what's going on behind the scenes, and not an attempt to solve a real world problem.

You need to think about how the code is executed with each page request. What happens on the server is that a class instance is created for each request and if the line of code
myButton.Click += new EventHandler(myButton_Click);
is conditional it means the event handler is not wired to the event on postback.
In other words if you write something like
<asp:Button ID="myButton" runat="server" OnClick="myButton_Click" />
This translates to the code you wrote and the event gets wired with each request.

The problem is, the event handler can only trigger when it IS a postback. The wiring of event handlers affects this instance of the class only. When a postback occurs, a new instance of your page is created and the event handler is no longer wired. You need to wire it in order for it to get triggered.
The best thing to do is always wire the event handlers. There's no reason not to.

If it is not a Postback, it means that the user just requested a page (HTTP Get request) with typing the URL in the browser (or clicking a link, or...).
If the user clicked on a button, then the browser makes a HTTP Post request, which on the server side, ASP.NET marks the page that is requested with setting the property IsPostBack to true of the page object.
See the answer on this question.

I guess what you intend to do is disable the button on postback.
You can do that by setting the enabled property to false.
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
myButton.Enabled = false;
}
}

checkbox chekced or unchecked does not trigger event

There is an exisiting page I am working on at where I work, and there is a checkbox in the ascx , and it has a CheckedChange event for it in its .cs The problem I am having with that page is that when i run the website and check the box, it never fires the event, instead it goes through the On_Load event and it never pass throgh the event... I am not sure why it is not firing the event...
<asp:CheckBox runat="server" ID="OptionSelected"
OnCheckedChanged="OptionSelected_CheckedChanged"
AutoPostBack="true" />
<asp:Label runat="server" ID="OptionHeader"></asp:Label>
protected void OptionSelected_CheckedChanged(object sender, EventArgs e)
{
//some code here
}
PS: This is a control ascx sorry, I forgot to mention. Also another symptom is that the page where that control is... it refreshes unexpectedly, clears some data (including the checkbox if it is checked) and cant figure out what it is causing it.
Any ideas of the reason why this might be happening? things i should look for?
public PortalInfoPortal myPortal
{
get
{
return portal.GetPortalInfo();
}
}
protected void Page_Load(object sender, EventArgs e)
{
//added this an nothing
OptionSelected.CheckedChanged += new EventHandler(OptionSelected_CheckedChanged);
if (myPortal != null)
{
lblOptionMsg.Text = "(" + myPortal.MaxOptionSelectedCharacters.ToString() + " char max)";
txtMessage.MaxLength = myPortal.MaxOptionSelectedCharacters;
var maxLength = myPortal.MaxOptionSelectedCharacters;
maxCheck.ValidationExpression = #"^[\s\S]{0," + maxLength.ToString() + "}$";
}
//There is no binding of any type here
}

you need to have viewstate turned on to have changed events fire. viewstate is how the server knows what the state of the control was when the page was originally served and before it was posted back. without this information, it doesn't know whether the value has changed. check to see if you have viewstate enabled.

Are you perhaps creating the usercontrol (using Page.LoadControl()) and adding it to the control tree dynamically and then forgetting that those steps need to be performed on every postback? Otherwise, the usercontrol no longer exists on postback and none of its events will be fired.

Calling a function before Page_Load

I have a button that calls function A()
When I click on it I want the calls to be made in that order:
A()
Page_Load()
Right now it's doing:
Page_Load()
A()
Is there a way around that or is it just by design and there's nothing I can do about it?

The easiest way to do this would be to use a HTML Submit button and check to see if it is in the Form on every postback in Page_Init
public void Page_Init(object o, EventArgs e)
{
if(!string.IsNullOrEmpty(Request.Form["MyButtonName"]))
{
A();
}
}
And in your ASP.NET code:
<Button Type="Submit" Name="MyButtonName" Value="Press Here To Do Stuff Early!" />
I think that will work.

Control events (such as the click events of buttons) are called after page_load. The controls are not guarenteed to be fully initialized prior to page_load. If you really need to call a function before page_load has been called based on whether a button has been pressed you'll have to examine the request to check if the button has been pressed (basically old school ASP)

You need to call your function in the Page_Init. Page_Init will happen before Page_Load.
Here's an Overview of the ASP.NET Page Lifecycle.

Not exactly: ASP.NET will always call Page_Load before handling postback events like Button_Click.
However, you can accomplish what you want by redirecting to your page after handling the postback event. (Using the Post-Redirect-Get pattern.)
Inside your Page_Load method, you can avoid running any relevant code twice by checking to see if it's a postback first:
if (!this.IsPostBack) {
// Do something resource-intensive that you only want to do on GETs
}

As Jeff Sternal answered, The Post-Redirect-Get pattern is a good way of solving a problem like this.
In my circumstances i had a calendar and if you clicked a date it would add that to a scheduler. The scheduler would have buttons on each new date that needed to have onclick functions tied to them.
Because the new row was being added with a linkbutton(on the calendar), in the code the new scheduler date was being added at the Postback event handling meaning that the new set of buttons wouldn't have a command tied to them.
The page life Cycle
Post Get Redirect

I don't think it's possible, at least, not in the way described by your question. When you click a button it will send a request to the server which in turn will start processing it, and follow the ASP.NET Page Lifecycle as posted by Joseph.
Alternatively you could try making an AJAX call to a page without reloading the current one you're on and do whatever processing you require.

This is what you want to do for Page Init is called before Page Load.
Take a look at the ASP.net Page Life Cycle
public void Page_Init(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
//CALL YOU FUNCTION A()
}
}
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
}
}

If your actual goal here is to have your "page loading code" happen after your event handler runs -- for example, if clicking your button changes something in your database, and you want the updated data to be reflected on the page when it loads -- then you could have your "page loading code" get called from a method that gets called later in the ASP.NET page life cycle than your event handler, such as Page_PreRender, instead of calling it from Page_Load.
For example, here's a simplified excerpt from an .aspx.cs page class that has a button event handler that runs before the page population logic, and a confirmation message that is visible on the page only after the button was clicked:
// Runs *before* the button event handler
protected void Page_Load() {
_myConfirmationMessage.Visible = false;
}
// Runs *after* the button event handler
protected void Page_PreRender() {
// (...Code to populate page controls with database data goes here...)
}
// Event handler for an asp:Button on the page
protected void myButton_Click(object sender, EventArgs e) {
// (...Code to update database data goes here...)
_myConfirmationMessage.Visible = true;
}