Web Forms :: Auto Generate Page Level Event Handlers?
Nov 1, 2010Inside VS2010 is there a way of auto generating page level event handler code?
View 2 RepliesInside VS2010 is there a way of auto generating page level event handler code?
View 2 RepliesI'm having a hard time understanding why the following code doesn't work. I'm sure it's something remedial that I'm missing or not understanding. I currently have a page that asks for user input. If, based on the input and logged in user, I find data from this page already in the database, I need to update the existing records rather than creating new ones, so I set a class-level bool to true. The problem is, when MyNextButton is clicked, PreviouslySubmitted is still false. So, I'm not sure how to make the value of this variable persist.
public partial class MyForm : System.Web.UI.Page
{
private bool PreviouslySubmitted;
protected void Page_Load(object sender, EventArgs e)
{
MyButton.Click +=
(o, i) =>
{
q = from a in db.TableA
where (a.SomeField == SomeValue)
select a;
if(q.Any())
{
PreviouslySubmitted = true;
//populate the form's fields with values from database for user to revise
}
}
MyNextButton.Click +=
(o, i) =>
{
//the value of PreviouslySubmitted is false at this point,
//even if I made sure it was set to true the previous postback
if(PreviouslySubmitted)
{
//update database
}
else
{
//insert into database
}
}
1) I know there are lots of web sites that describe in what order events are called during the Asp.Net page life-cycle. But is there also a tool, perhaps Reflector, that would enable me to figure out by myself in what order are ALL the page's events and their event handlers called during the page's life cycle? 2) Would you say that trying to figure out exactly what is going on under the hood is a good idea or a waste of time? To clarify - I'd like to figure out exactly what is going on when a control tree is build - thus all the method calls, all the events called etc needed for control tree to be build ( I imagine there are hundreds or perhaps thousands lines of code written just for building a control tree).
View 4 RepliesI have a ASP.NET content page where the master page is set dynamically. Both master pages contain a print button and an associated event handler for the click event of the button. Unfortunately I receive a run-time error when I attempt to dynamically access the event from the master page that was not initially assigned. Below are code snippets:
Page_Load():
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim strPageTitle As String = "Evaluator Data Form - Instructions"
If Page.MasterPageFile.Contains("masEvaluators.master") Then
Dim mp As Evaluators_masEvaluators = CType(Me.Master, Evaluators_masEvaluators)
[code]....
which produces the following error when I load the page and reference the "masStaff.master" master page:
System.InvalidCastException: Unable to cast object of type 'ASP.staff_masstaff_master' to type 'Evaluators_masEvaluators'. at Evaluators_EDF_Instructions.Page_Load....
I can solve the problem by adding a print button to the content page, but that defeats the purpose of using a master page.
I have project in asp.net with sql server backend.i want to auto generate a number for particular column.with the auto generated number i want to insert some other data in the same row same table. on button click event.details
railway PNR no.:- want to autogenerat
passenger details:- want to inserted simultaneously
I have a fairly complex web app which has two levels of master page. The top level provides a nav bar constructed from a Menu control across the top of the page. Second level master pages provide menus down the side. It all works well.
On both Menu controls, I need to handle the MenuItemClick event. This works fine on the Menu controls on the second-level master pages. However, the Menu on the top level master does not raise the event at all.
This web site makes extensive use of Ajax and the top-level master page contains the ScriptManager. Before I go to all the work of creating a much simpler test site, why the Menu control is not raising the MenuItemClick event?
Here is the markup for the Menu in the top-level master:
[Code]....
Here is the MenuItemClick event handler:
[Code]....
The logging call in the event handler never gets called. Equivalent code in the Menu on the second-level master does get called.
I have to handle error related to web application. I am not sure how its works. I am thinking that I will add an error page (error.aspx) and in global.asax ,application_onError, I will redirecting the user to error page and that should be enough ! i mean it will handle error automatically.
View 4 RepliesI am making an application in which i use button images instead of button control in web forms.
So, How can i access event handler through this image link ?
Ex.: For Button Control, there si a event handler called button_Click().
So. Just by pressing button control, i can access this event handler.
I want to achive this by clicking on link i.e <a> anchor tag.
I've been working on a web form that has lost it's ability to respond to most event handlers, though code that I write in Page_Load still fires. No button click or text changed events will fire. This has been working for months, and suddenly stopped. I did a windiff comparison to an older version of the webform, and don't see anything suspicious.
View 4 RepliesI am creating a hierarchial grid dynamically. I was able to add a gridview within a gridview. Now how can I create the gridview's rowcreated event handler programatically? I need it to be dynamic, depending on the number of levels of hierarchy I will add gridviews and their events. How can I do it?
the event names will be dynamic like GridView*_RowCreated.. where * will replace by a number of gridviews.
let me know "Is there any method to check whether a control was attached with any Event Handlers or not"?
View 3 Repliesreading on the forums about assigning event handlers to controls that are dynamically created via code and am just not getting anywhere.In my particular case, I'm rolling through a directory of images and creating ImageButton controls on the fly and want to assign the OnCommand event to a single handler.Then, by using the CommandName (which is different for each control) I can figure out which ImageButton was clicked and act accordingly.
The snippet below (which can be found in many posts on this topic) is inside a foreach which loops through the directory and gets each FileInfo (fi).Each is then added to a PlaceHolder (phImages).
[Code]...
This code compiles and runs but the event handler is never invoked when an ImageButton is clicked. I believe this is because you cannot, without some coding I'm not familiar enough to do yet, assign a handler to multiple controls.I say this because I ran into a similar problem in a Silverlight app I wrote and had to use a lambda (=>) operator to do something similar (although I admit to not knowing enough about this to know if this situation is the same).
The textbox has an onblur event (the workings of the onblur event are irrelevant), and an associated RequiredFieldValidator. This code functions exactly as it should. However,if in the body onload event I simply raise an alert of the innerHTML of tr1 or td1, the onblur event does not appear (but it does work, and can be seen when I view source in IE7). If I remove the RequiredFieldValidator, the onblur event handler is shown in the alert, or if I retain the validator but change onblur to onfocus, then the event handler also appears in the alert. I need this to work as when the user increases the Quantity, duplicates of the table row are added (I have tried both cloneNode, and setting the innerHTML of each new table cell to that of the original, but as my alert proves, the onblur event handler is not included in what is copied). The same problem also occurs with onchange for select tags with validators. I am using Visual Studio 2008 (.Net
2), IE7 and IIS 7.
[Code]....
i have three text boxes. one is for Rate , second one is for Quantity and third one is for Amount. when i am entering value in two text boxes. after press tab key multiplication of these two text boxes generated in third text box(Amount).
View 3 RepliesI have a situation where I dynamically load one of twenty user controls at a time in an ASP.net web page. Based on much reading I've done, I understand that I am to reload the user control upon postback via the Page_Init event handler. This I've done and it seems to work fine.
But now I would like to wire up assorted controls in the user controls such that when the value of each is changed, an event is fired and the web page is notified. Here's an example of how I'm doing that:
userControl.NewData_Handler += new EventHandler(UserControl_NewData_Handler);
There's a problem though. Because the user control is being done in Page_Init (ie. before Page_Load) I don't believe that a line of code such as the one above can function yet.
So I'm wondering what the best practice to do this is. It occurred to me that perhaps I could execute the line in the Page_Load event handler but I'm not sure if that's correct or not.
Can anyone clarify to me the difference between the following:
1.
{
// ...
Button b = new Button();
b.Click += new RoutedEventHandler(b_Click);
}
void b_Click(object sender, RoutedEventArgs e) { //do stuff...... }
2.
{
// ...
Button b = new Button();
b.Click += a_Click;
}
void a_Click(object sender, RoutedEventArgs e) { //do stuff...... }
I'm curious about the pros and cons when subscribing to event handlers.
<asp:DropDownList id="DropDownList1" runat="server" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged" />
vs
protected void Page_Init(object sender, EventArgs e)[code]...
How to generate a employee code in textbox automatically while in run time in web application.......when i run the page it will check the employee code in the database and it automatically shows the next value in the textbox how?
View 1 RepliesVS 2008 - create event handlers in C#? but i cant get this:
View 19 RepliesI've been programming ASP.NET for a number of years and have got into the habit of using the public access modifier when writing event handlers for nested controls. e.g.
LinkButton ln = new LinkButton();
ln.Click += new EventHandler(LinkClick);
....
public void LinkClick(object sender, EventArgs e)
I think I started using public because I ran into errors when using other modifiers. Is this the correct one to use here? Does it depend whether you're writing a Page / UserControl / other?
I want to add event handlers programmatically to the server controls rather than using their predefined OnClick properties, etc. But which would be considered a better practice for defining handlers:
Define them in Page_Init
Define them in Page_Load
Index outof range?GridView2.Columns[6] as BoundField I use Auto-generate field .
How to manipulate GridView2.Columns as BoundField with auto-generate field?
[code]....
My GridView uses auto generate Edit & Delete command button. And then program the insert button. I want to do something when users click the Edit button so I wrote something like this:
[Code]....
When click the Insert button in the Footer, the program works fine. But when trying to click the auto generate Edit button, the following statement failed with the exception stated in the code above:
first_name = gvAgent.SelectedRow.FindControl("txtEditFName")
I have an implementation for my website to have facebook single sign on, using their javascript sdk.The javascript adds the cookie and I deal with it fine.The question is related to when an user logs out of facebook, I would expect the auth.sessionChange or auth.logout events to fire, but that only occurs when the page is refreshed.As my implementation is done server-side, this means that after the user logs out of facebook they can access one secure page one more time before being properly logged out.Is this the normal case or do these events usually fire up straight away and I'm maybe doing something incorrect in configuration of the facebook app?
View 1 RepliesIs it mandatory to pass the Success and Failure method names as parameters while calling server side methods using PageMethods in client script.
I referred to article [URL] ....