I have asp.net page which loads the user controls at run time I want to capture the save/cancel event of page on the user control.
User control will be load at run time so, for further development I don't want to change my code on page level.
Any help.
I solve it, with the help of observer pattern but with some more modification because my challenge is Page don't know which user control will be load on run-time in its place holder.
I create change-manager which holds the Observers references with their intended types(submit,cancel,viewonly)
Page holds the reference of change-manager and call the notify of change manager with (eventtype(enum),response(this.response object)) then change manager calls the update method In this method call Observers, kept in the dictionary of change-manager.
Iterate the dictionary and call their updates according to their interested event types.
Now I am free to remember the user-control reference of any type of casting.
see below example of get user control from page you need to use public modifier
///user control code see event is public
public void btn1_Click(object sender, EventArgs e)
{
///do you stuff
}
/// page code
protected void Page_Load(object sender, EventArgs e)
{
uc1.btn1_Click(sender,e);
}
Related
Let's say that in an ASP.NET .aspx page I have the Page Load method and another method for a button click event.
In the Page Load method I'm checking if the user is logged in by checking the Session. Whether he is or not, I'm storing the result in a Global Variable.
Boolean isGuest = false;
protected void Page_Load(object sender, EventArgs e) {
if(Session["id"]==null)
isGuest = true;
else
isGuest = false;
}
Let's say 20 minutes have passed, and I don't know if the Session has terminated or not, and then I click a Button, the event goes like this:
protected void Button_Click(object sender, EventArgs e) {
if(isGuest==false)
//do something
else
// do another thing
}
My Question is : When I'm clicking the button, does ASP.NET go through the Page_Load method again (check isGuest again) or it simply executes what's inside the Button_Click method, means, it uses a Boolean isGuest that could be false, but in reality the session is terminated, means it should be true.
Page_Load is triggered always before the control events.
Have a look: ASP.NET Page Life Cycle Overview
Side-note: If you want to do things only on the first load and not on every postback you have to check the IsPostBack property.
You can:
Define your own class with the UserID, and other profile properties;
Add that class to session in the global.asax session started event Session["NameReferingToYourClass"] = new YourClass();
Set a member variable to your session object early in the page life cycle mYourClass = Session["NameReferingToYourClass"] casted if you need to;
Then you can make any changes to your class anywhere in the code your member variable is available;
Save back your class with all the changes into session on the Page.Unload(..){ Session["NameReferingToYourClass"] = mYourClass.
This way you are using your class properties in your code, including UserId, pretty much like a windows application, there will be no mentioning of session anywhere else in your code.
In my application, I have a form that users fill out, then gets approved by a manager. I have various types of forms that all use the same process, so the approval buttons are all done via a user control (which includes the functionality to update the data in the database and call the postback).
However, once I click on the "Approve" button (which is in the user control), the form information doesn't update (it still says "unapproved"). A postback is definitely happening, but not sure why the page isn't updating properly.
I can confirm that the change are being made - when I manually reload the page, it gets updated - but not on the post back.
What am I missing here?
My page:
protected void Page_Load(object sender, EventArgs e)
{
int ID;
// ensure that there's an ID set in the query string
if (Int32.TryParse(Request.QueryString["ID"], out ID))
PopulatePage(ID);
else
Response.Redirect("~/Default.aspx");
}
}
protected void PopulatePage(int ID)
{
using (WOLinqClassesDataContext db = new WOLinqClassesDataContext())
{
lblStatus.Text = wo.Workorder.status;
....
}
}
I think that the Page_Load happens before the code in the submit button. To check this just use a couple of breakpoints. So the page loads the old data since the new data are not saved yet.
You should call a method to load the data inside the OnClick method of the Approve button.
After you've submitted the changes to the database, try running db.Refresh(RefreshMode.OverwriteCurrentValues) to force the changes to be reloaded into the data context.
I have a site with multiple pages, not necessarily heirarchical. I want to query the user's identity (using AD...) whenever the user first enters the site, and create session state variables for the convenience of other pages as needed. A user could possibly enter the site without going through the default.aspx page, so I thought I'd put the code in the Master Page's code-behind.
On the assumption this is a good idea, versus some sort of static class that maintains this information, I started setting it up, but found the Master Page code-behind doesn't always seem to get fired when I enter the site. Is this a debugging phenomenon, or am I right, and the Master Page is the wrong place to put this code...?
I would recommend using the Global.asax class. You'll need to add it to your web app if it's not already there. Once you have it, you can then use the various events (session start and end, app start and end and error) to implement business logic particular to what you need exactly.
I tend to monkey around with the logged in user in the Application_PreRequestHandlerExecute event of the global.asax. This will allow you to look at the User Principle (eg - User.Identity.Name) to see who is logged in (or if they're not logged in) and do what you need to (such as set Session information for the user, etc.).
Here's a tidbit of code I've got on one .NET web app that uses the Global.asax for storing user data in the Session.
protected void Application_PreRequestHandlerExecute(Object sender, EventArgs e) {
if (Context.Handler is IRequiresSessionState || Context.Handler is IReadOnlySessionState) {
SetUserItem();
}
}
private void SetUserItem() {
if (Session["UserItem"] == null)
Server.Execute("~/SetSessionUserObj.aspx", true);
}
... and then the SetSessionUserObj.aspx.cs
protected void Page_Load(object sender, EventArgs e) {
string ID = User.Identity.Name;
MyUser myUser = new MyUser();
UserItem userItem = myUser.GetUserItemByID(ID);
if (userItem != null) {
Session["UserItem"] = userItem;
}
}
This is just one manner that you can go about accessing a user's identity in the global.asax. You don't necessarily have to go about doing a Server.Execute to set user data (I just did it for other reasons that fall outside the scope of this question).
Good luck.
I'm recently mining a website to build some database. I already built a python script parsing retrieved information but the problem is that it requrires a query word to retrieve web pages which contain information I want to see. And this page is in POST method so I cannot see how this page retrieves a page list.
To describe an outline for your clear understanding:
1. on inputKeyword.aspx : This contains a form to input a query(let's say ID)
When I input an ID and press search, it retrievs a
relevant list
2. Press Search
3. on inputKeyword.aspx : A relevant list is showed on the same aspx page
(which means POST method), so I cannot see how this query
works on inputKeyword.aspx page.
It would be so much easier if this webpage is in GET method, since I can simply hook a url with queries, but it's not possible in POST method.
Is there any way that I can open step #3 skipping step #1 and #2?
The webpage is built in asp.net but there's no restriction on languages as long as there's way to do this.
If I understand correctly you want to be able to accept a an ID as part of your query string. eg
http://your.domain.com/inputKeyword.aspx?ID=555
So in the pages load event you can check the request object for query params, ie Request.QueryString[param] as the following example shows
protected void Page_Load(object sender, EventArgs e)
{
string id = Request.QueryString["ID"];
if (!string.IsEmptyOrNull(id))
{
//do something with the requested identifier
}
}
Note: you can use Page.IsPostBack() to determine if the page is being hit for the first time or is posting back as a result of a button click.
To get your Search button to behave correctly you have a couple of options. For example; you can use javascript to capture the buttons onclick event and redirect the page to itself with the url amended to include the identifier from the id textbox.
But perhaps the following is the easiest, keeping the code all server-side:
private _identifer string;
protected void Page_Load(object sender, EventArgs e)
{
string id = Request.QueryString["ID"];
if (!string.IsEmptyOrNull(id))
{
_identifer = id;
}
}
protected void SearchButton_Click(object sender, EventArgs e)
{
_identifer = IdentiferTextbox.Text;
}
protected void Page_PreRender(object sender, EventArgs e)
{
if (!string.IsEmptyOrNull(_identifer))
{
PopulateListForidentifer(_identifer);
}
}
Basically the example shows that you can cope with scenarios. ASP.Net's page life cycle means that events are processed in the following order Page_Load -> Control Events (eg button click) -> Page PreRender.
If the page is hit for the first time without an identifier in the url, PopulateListForidentifer method isn't called since _identifer is never set.
But if the url contains an identifier then _identifer is set in the page load event, when the page pre-render is called PopulateListForidentifer will be called.
Finally if the page is posting back to itself because the search button has been hit then the click handler is called and _identifer is set to the content of the IdentiferTextbox; the pages prerender is called and also PopulateListForidentifer. Note this would override the point about ie when the identifer was passing as part of the url.
From what I understand, it seems you want to simulate the HTTP Post operation in your Search form, where by without entering the ID and clicking search, you directely want to have access to the search results.
Here is a Blog Post by Scott Hanselman, where he discusses a similar topic using WebClient.
You may also want to check this thread
I am getting the following error
'Event handlers can only be bound to HttpApplication events during IHttpModule initialization.' at the following code (line in bold or double **)
protected void Application_BeginRequest(object sender, EventArgs e)
{
HttpApplication app = (HttpApplication)sender;
**app.EndRequest += new EventHandler(Application_EndRequest);**
}
protected void Application_EndRequest(object sender, EventArgs e)
{
UnitOfWork.Commit();
}
which is mentioned in Global.asax file. Can anybody figure out, where I am lacking? Thanks.
The event handler lives the entire life of your application, so, you only need to add it once not add it every request. The event itself will fire every request, and the only-one handler will be called every time the event is raised.
Add it to Application_Start in global.asax not Application_BeginRequest, or better, create an HTTP Module instead.
Also, I think you may not even need an event handler. The method with current name will be called by convention similar to Page/Control AutoEventWireup (like Page_Load). Just note that this might have issues in ASP.NET MVC applications as some people report. So, my suggestion is to rename the function, add the event handler in Application_Start, or better in a new HTTP Module you create.
Try to comment out line marked with "**". Asp.Net will call appropriate methods by itself if followed by naming conventions: "{Scope}"_"{Event}", where "{Scope}" is Application if you want to handle application level events or "Session" if you want to handle session level events, and "{Event}" is name of the event, like Start, End, etc.
More info: http://msdn.microsoft.com/en-us/library/bb470252.aspx#Stages