Web Forms :: Page Does Postback, Refresh But Event Handler Method Is Not Executed
Apr 6, 2010
I have problem with user control: MyCollection : UserControl
MyCollection contains:
[code]....
Works fine unless I register event for some button:
button1.Click += ...
When click on button, nothing happens - page does postback, refresh but event handler method is not executed. Generated HTML is bit strange. Every page control has correctly generated ClientID including parent container ID.
Button in this collection MyCollection has odd ClientID - itemsAddresses$button1
I'm learning asp.net page life cycle. I find an article on MSDN [URL] It says that If the request is a postback, control event handlers are called. After that, the Validate method of all validator controls is called, which sets the IsValid property of individual validator controls and of the page. And the picture in the article also says validate fires after event handling. If this is true how can I get status of validator when I handling the event?
I have a custom class (ServerSideValidator.vb) that validates user input on server side (it doesn't use any of the .NET built in validators, therefore Page.Validate() is not an option for me). I am calling the Validate() method on page.IsPostback event and the class performs without any problem
My issue is, when validation fails (returns false), I want to stop the postback event handler from firing, but load the page along with all the controls and user-input values in them. If I do, Response.End(), the page comes up blank. I can programmatically instruct the page to go to the previous page (original form before postback), but it loses all user-inputs.
I thought of creating a global boolean variable in the page code behind file and check the value before performing any postback method, but this approach takes away from my plan to provide all functionalities inside the class itself. The page object is being referenced to ServerSideValidator.
Seems like all the postback related properties/variables I come across inside Page class are 'Readonly' and I can't assign value(s) to control/prevent postback event from firing.
I have a asp.net page with a button, the event the button needs to perform on it's click event needs to vary, dependant on what options are selected further up the page. The button itself is included in the master page, and it's actions are affected by selections made in the child page.
To do this, I have a method in the master page, that is called by the child page, when a users presses a button, that passes the Eventhandler to be used by that button, that is then assigned to masterpage eventhandler for that button:
public void assignEvent( EventHandler saveEvent) { this.SaveButtonEvent+= saveEvent }
Then, when the save button on the master page, it calls that eventhandler
The event handler is assigned ok in the first section of code, however because pressing the save button causes a postback, the SaveButtonEvent event handler is set back to being null, and so nothing happens.
How can I preserve the contents of SaveButtonEvent Event Handler during postback, or is there a better way to be doing this?
EDIT:
I can get this to work by saving the EventHandler to the session, but this doesn't seem like a great idea.
I have a page books.aspx that has a control named authors.ascx.
Inside the authors control there is a "select" button I want to add some kind of listener or event handler (not sure of the correct terminology) so on the parent page (books.aspx) I can respond to the "select" button being clicked.
I have to pass the authorID from the user control to the parent page.
In my authors.ascx control I just created this event:
[Code]....
Now I need to write the function for SelectAuthorBtnClick and I think add some kind of listener in the parent page to listen and handle the event.
I have a control which has an ImageButton which is tied to an OnClick event... Upon clicking this control, a postback is performed and the event handler is not called. AutoEventWireup is set to true, and I've double checked spelling etc.... We haven't touched this control in over a year and it has been working fine until a couple of weeks ago.
We have made changes to controls which load this control... so I'm wondering, what kind of changes could we have made to stop this event handler from being called? There is quite a bit of Javascript going on, so this could be the culprit too...
I have a page which allows the user to send email. After they click the submit button, I display a confirmation message. However, if the user clicks the browser's Refresh button once the confirmation message is displayed, the email is sent a second time (or a third, fourth, fifth, etc.). What can I do to prevent the Refresh button from resending the email?
I've created a UserControl that is dynamically placed onto my page during the Init event. It populates and works great, but I'm left scratching my head at how to retrieve data from it during a postback.
It's effectively a multipick combobox that is manipulated entirely using clientside JavaScript (I'm using jQuery heavily). Inside the control container element, I render an empty DIV element that contains all of the selected items. As the user selects items, I generate DIVs within that container DIV that includes some markup. Of interest to me on the server side are the contents of a couple of INPUT fields.
After selecting an item, the rendered HTML looks something like:
[code]....
I may be completely off track and this may actually be impossible (or a stupid idea). The only alternative I can think of is to emit actual ASP.NET controls and hook the built-in event handlers.
I am building a web site with visual web developer 2010
I have a class (autoButton) that adds a button to a panel (on Default.aspx) and a handler w/i the same class (classifyEventHandler)
The button appears fine, but when clicked the even doesnt fire, what am I doing wrong?
I tried locating the event handler in default.aspx, but it was not found :P
Imports Microsoft.VisualBasic Public Class autoButton Public Sub makeClassifyButton(ByVal theCell As Object) Dim myButton As New Button myButton.Text = "classify" myButton.ID = "b_classify_" + theCell.ID AddHandler myButton.Click, AddressOf classifyEventHandler theCell.Controls.Add(myButton) End Sub Private Sub classifyEventHandler(ByVal sender As Object, ByVal e As EventArgs) MsgBox("done?!") End Sub End Class
Is there a technical reason for the existence of Page.PreLoad or is this just convenience to have a place where you can neatly place code that always have to be executed before the Load code? Is there a difference between adding code in the PreLoad event handler and adding code at the top of the Load event handler? And what would be a typical scenario where you use PreLoad?
I have a masterpage with a checkout total for goods. WHen i add to the cart i press the button which adds to the cart but i want to refresh the checkout total on my masterpage.how can i do this on postback?if i change page the total updates fine
I've got a page with several gridviews that populate on page load. After user makes choices with radio buttons insid the gridview and presses submit I would liek the page to refresh and reload all gridviews.
postback page load loop and data doesn't get saved to the DB so I have to use If not Page.IsPostback then to avoid the loop.
After pressing submit, if I navigate to another page, then navigate back, I get the desired result I'm looking for a fresh reload.
how can I have the entire page reload fresh after the submit button is pressed? (it has to save data first then reload)
When I click on the aspx Submit Button, the file selected in Silverlight control should be uploaded and after the completion of upload, the Server side event should get called.
I have a master page that contains a navigational menu, made up of nested databound repeaters. Buttons are created for the outer-most repeater's items. When the user clicks on one of these buttons, the content page loads and a label within this content page changes to reflect the text from the button that was clicked. In other words - click a button, load the page, change the label on the page to the text on the button. I have tried also changing the initialization on the content page from Page_Load to Page_PreInit to Page_Init, and nothing seems to matter as I'd like to move on in this project! Code follows:
Master Page (Site.Master):
[Code]....
Content Page (BatchView.aspx):
[Code]....
The problem is, whenever a button is clicked, it changes the title of the master page to 'Not Working', which lets me know that the TeamChosen eventhandler is null!
I have a problem when I try to pass in paramaters for a report in my report viewer. I have set up the ObjectDataSource and set the paramaters for 3 text boxes that are on the page. The only way I have found to set the paramaters for the report is the user must fill in the paramaters and hit the refresh button on the Report Viewer toolbar ,but I would like to have the user click a asp.net button insted. Is there anyway to call the refresh method from codebehind?
I've read that OnClick is executed on the server and onClientClick is executed on the client. Is it better to use OnClientClick to do something like close a modal popup?
If my understanding is correct then this would avoid a trip to the server to accomplish the same task. This would be great for something that doesn't need to make a round trip to the server and back.
