Web Forms :: How To Use AddHandler To Dynamically Assign Events To Dynamically Created Buttons
Feb 14, 2011
I have a website that sales associates access to view account information with clients. S.A's can only view information for accounts that they are tied to. Some clients have more than one account, S.A's can be tied to more than one account, but not all accounts of one client need to be tied to one S.A.
On the account info pages, I have account numbers (dynamically displayed labels) displayed of other accounts that the account client is associated with, which the S.A's can see. I'm modding this so that if the S.A has viewing permissions of any of the other accounts on that list of accounts, that instead of a label being displayed, a button directing them to that account page will display instead. In order for this to work, I have to attach a security function to the button, otherwise the page will blow out on the S.A's.
So I'm running a piece that is displaying a button instead of a label, which is working fine. My problem is when I try to attach the security event to the dynamically displayed buttons. It seems that the page just posts back and doesn't execute my code at all.
On my Page_Load, I'm running this after the buttons and labels are displayed:
For x = 0 to tblAccountList.Rows.Count - 1
'use a try to target the button, use catch to handle if it's instead a label, only one cell per row.
Try
Dim accountLink as Button = tblAccountList.Rows(x).Controls(0)
Addhandler accountLink.Click, AddressOf Me.PermissionViewCheck
Catch ex as InvalidCastException
Continue For
End Try
Next
I don't have any code checking for postbacks or anything like that, but the "PermissionViewCheck" event never fires and just reposts the page.
m new to .NET. I'm trying to create a button dynamically with event by original button. The original button's click event response creates a button. The new button has a click event attached with a test message.What I have to do is onclick change background color of dynamically created button and grab id value to delete when button delete is clicked. Unfortunately, when I click the dynamically attached button,
I created a web site with admin control with C# ASP.Net. Admin can create a new button1 with button2.I did this. but when admin login again the created button is not seen.I guess I should save this created button at SQL Server but how should I do.
I'm trying to create a button dynamically with event by original button. The original button's click event response creates a button. The new button has a click event attached with a test message.What I have to do is onclick change background color of dynamically created button and grab id value to delete when button delete is clicked. Unfortunately, when I click the dynamically attached button, nothing happens.
I've dynamically created 3 checkboxes as you can see in the code below. I also wrote an event handler below. When I run the code, the 3 checkboxes show up, but the event handling does not work right. Whenever there is postback from any of the 3 checkboxes, Label1 reflects the state of checkbox #3, no matter if I toggle checkbox #1 or #2. I put the code I have under Page_Init into Page_Load instead, but makes no difference either way.
The bottom line is, I want the event handler to know exactly which of the 3 checkboxes is firing the event so that Label1 can reflect that.
I'm working on an ASP.NET project in which the vast majority of the forms are generated dynamically at run time (form definitions are stored in a DB for customizability). Therefore, I have to dynamically create and add my controls to the Page every time OnLoad fires, regardless of IsPostBack. This has been working just fine and .NET takes care of managing ViewState for these controls.
//1. call service layer to retrieve form definition //2. create and add controls to page container }
I have a new requirement in which if a user clicks on a given button (this button is created at design time) the page should be re-rendered in a slightly different way. So in addition to the code that executes in OnLoad (i.e. RenderDynamicControls()), I have this code:
My question is, is this really the only way to accomplish what I'm after? It seems beyond hacky to effectively render the form twice simply to respond to a button click. I gather from my research that this is simply how the page-lifecycle works in ASP.NET: Namely, that OnLoad must fire on every Postback before child events are invoked. Still, it's worthwhile to check with the SO community before having to drink the kool-aid.
On a related note, once I get this feature completed, I'm planning on throwing an UpdatePanel on the page to perform the page updates via Ajax.
I'm creating an quiz application which queries the database and extracts the questions and choices. I use dynamically created controls such as a checkbox list and fill the values dynamically. How do I do this? Right now I have these functions:
array_random_init(); this creates a 10 element integer array from 1-20 - extract_question(i): this extracts a question indexed at i in DB, I created the controls and set the appropriate text in this function. - validate_question(i); this is called by button_click and validates the question i according to DB.
I understand I have to recreate the controls in Page_init on postback, but what should it look like? Do I need to add "if IsPostBack" in page_init, or do I create the controls in page_init() and reset their properties in page_load when I use extract_question(i)? Also, I cannot seem to clear the selected boxes on postback, I added page directive "enableviewstate=false" but it doesn't work.
I've added AddHandler to dynamic controls in code behind but when I (for example) select an item from the ajax combobox (selectedIndedChanged) nothing happens.
in my asp.net+vb+access web i am having a page in which i am counting and displying the numbers in text boxes/labels. it works fine.
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim connectString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=C:webWing.mdb" Dim con As OleDbConnection = New OleDbConnection(connectString)
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i want to amend the value with the value of the text boxes that i had tried manually it works fine.
I have a writing a web page that will use several different types of control. The control types will depend on the data being read from a SQL database. The following is my code that decides what control to add to the page:
Select myReader.GetString(1) Case "DatePicker" Dim bdpAnswer As BasicFrame.WebControls.BasicDatePicker = New BasicFrame.WebControls.BasicDatePicker() bdpAnswer.DateFormat = "dd/MM/yyyy" divAnswerContainer.Controls.Add(bdpAnswer) Answers.Controls.Add(divAnswerContainer) Case "DropDownList" Dim ddlAnswer As DropDownList = New DropDownList() divAnswerContainer.Controls.Add(ddlAnswer) Answers.Controls.Add(divAnswerContainer) Case "RadioButton" Dim rbAnswer As RadioButton = New RadioButton() divAnswerContainer.Controls.Add(rbAnswer) Answers.Controls.Add(divAnswerContainer) Case "TextBox" Dim tbAnswer As TextBox = New TextBox() divAnswerContainer.Controls.Add(tbAnswer) Answers.Controls.Add(divAnswerContainer) End Select
There is a dropdown 'ddlpageName' on a page where all the pages are listed.
Now When I select the particular page name from the ddlpagename, all the events (like page_load, grid events ,dropdown events) should be listed in other dropdown named ddlevent.
I got GridView with 2 columns both are Template field with drop down list. What I need to do is someting like when user select course 3/3A/2A/2B , the type column will auto select pratical option dynamically. When select RTT /FTT/BTT , the type column will select Theory option. Can someone tell me how to work on this thing.
I need to show the order summary at the end of the transaction in my application.Here i need to design a htm page in my application and i need to dynamically assign the table in the html page in my application.
What I am trying to achieve here is as follows. I have a mailing system that works great, I have users from a datasource being looped through and having that message sent to the users that are in that datasource. But my question now is, because I will have multiple queries/datasources (for different users in the mailing system for different purposes), is there a way I can bind a datasource to a radio button and then have that selected radio button be used for the mailing datasource?
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As you can see with this line Dim dt As DataTable = DirectCast((DatasourceOptInMembers.Select(DataSourceSelectArguments.Empty)), DataView).Table I want to have the DatasourceOptInMembers dynamic vs a statically assigned datasource. So baically if another options is selected it will use that datasource instead.It appears simple, although unsure of how to construct this.
My application I am using pagination.Using pagination i bind the records with listview control.
I generate the buttons dynamically according to the number of pages which is calculated from number of records returned from dataSource.when i click on a dynamically generated button its corresponding event handlers methods should get evaluated.Since asp.net page is stateless I can't keep the state of that dynamic controls after any postback.
Just Now I have seen the Article "How to get the Id of Control that cause postback in asp.net?". I got some idea from that article. Any example for "Creating link buttons dynamically and handling its corresponding event handler in Asp.Net".
I'm creating 14 textboxes for every day in a month and user can select the month so i have o create them dynamically. But i can't reach the values in the textboxes.
I have a tree view with checkboxes for leaf nodes. If i click on checkboxes, I am creating some html controls dynamically. And in other static button click event I need to get an ID's of those dynamically created controls.
I have a web user control with dynamic LinkButton think an event in which you assign events to them (LinkButton.Click + = new EventHandler (Method)).The problem is that these events do not run, I did test creating and if you run statically.Why is it??I need to be created dynamically at runtime.For Examples :
for (int i = 0; i <= 5; i++) { Button boton = new Button();
i have created the dynamic tree view in ASP.NET using C#, but i have to add url's in the dynamically created treeview. can any one give the basic coding for it with example..
I have a link button let's say LB1 wherein on click of the LB1 a modalpopupextendar will open up with a textbox where we can enter the message and onclick of Ok button the entered message will be saved. Let's say we have repeated the above steps for thrice. So there will be three rows created in DB. Let's say column name UID is the primary key.Now, I am displaying the each message inside a panel along with Link Button(LB2) which is created dynamically while reading the text. So,The first row will contain
UID:1 Message:Message1
Comments:Comments Link Button(LB2)
The second row will contain
UID:2 Message:Message2
Comments:Comments Link Button(LB2)
The third row will contain
UID:3 Message:Message3
Comments:Comments Link Button(LB2)
When I click on Comments Link Button(LB2) a modalpopupextendar will popup wherein we can enter the comments. Let's say we are clicking on LinkButton of Message 1, a pop up opens and after entering comments and ok button the comments are saved for all the three messages instead of saving it for message 1, i.e I couldn't find the unique id of the message.
