I have an update panel that contains a textbox and some labels, which is contained within a custom user control, which is part of a step in a wizard control. At the moment when the user enters the textbox on the step the update panel fires when the user clicks on the textbox. However, what I want to do is to execute the update panel when the step loads as the textbox value is populated when from the previous step.
Is there away of automatically executing the update panel on the page load method?
You can call the Update() method in code behind, but only if you set the UpdateMode to Conditional. Also check that ChildrenAsTriggers is set to false.
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I have a page that has a user control in it. In the user control text boxes generate dynamically in a place holder and there is a button that will save all of them into the database. But here is the problem: When i click on save button, first, my page's page load event runs, then it loads user control, then user control page load event runs. so text boxes loose their content from last page. any idea?
Within your Page_Load, continue to always generate your textbox controls (regardless of IsPostBack). However within the control, only set an initial value if IsPostBack = false. That way when IsPostBack is true the textbox will take it's value from the ViewState instead.
I have a button on my page and and few textboxes which alters their context on page_load event. when I open the page for the first time it loads random data from a database to textboxes with a function in pageload and also I create those textboxes dynamically. what I want is to make some changes on textboxes texts and click the button than send new context of textboxes to database. But when I click on button, PageLoad event fires again and It regenerates the textboxes and the context of them alter naturally since they are newly created textboxes. I tried to use "if(!Page.isPostBack)" in pageload but then the textboxes and related objects are not being created and they become null.
how can I overcome this problem?
best thing I can think of is to find some way to fire buttons click event without firing PageLoad event, but I dont know how can I do it.
any help would be appreciated;)
From Comments
Can you regenerate the Textbox on each Page load Execution? and data assignment to these Textbox should be under !Page.IsPostback. All you have to do is to keep the IDs of the Textbox in ViewState only first time page load and next regeneration of Textbox will have the previous stored ID and you also have to store the ID corresponding data in ViewState. Makes sense?
I have a button and a panel. When the user clicks the button it loads a usercontrol and adds it to panel.Controls. I need to bind a grid in the usercontrol when the usercontrol first loads (Page_Load) but not when the user clicks a button inside the usercontrol, aka triggers a postback in the usercontrol. I can't use Page.IsPostback because it returns true when the user clicks the main button which loads the usercontrol. What can I do?
It's primitive, but you can check for any control that caused the postback by comparing the value coming from:
Request.Form.Get("__EVENTTARGET")
This returns the uniqueID of the targeted control; check this to determine which button caused the postback, and act accordingly.
You can give the buttons inside of the user control a CommandName and check the value of the CommandName. You can also check the type on object sender to determine the control that caused the post back.
Don't forget that you will have to re-add the user control on each post back after it is dynamically created (in an event that occurs before Page Load), so you will need to implement a mechanism to determine that the user control was added in the panel.
I have an update panel that contains a repeater that calls a user control into each row. When I click a button inside the user control, the page does not refresh at all, only when I reload it completely. How can I make the update panel refresh from user control's button click?
Phairoh is correct that your button needs to successfully cause a PostBack.
There are three things that affect when a UpdatePanel is updated:
The UpdateMode property - This takes two possible values, Always and Conditional.
If it is set to Always then any postback o the page will cause the UpdatePanel to update.
If it is set to Conditional then the UpdatePanel is only updated when the UpdatePanel's Update method is called or when one of the UpdatePanel's triggers does a postback.
The Triggers proroperty - Defines which controls will cause the UpdatePanel to be updated when UpdateMode is set to Conditional.
The ChildrenAsTriggers property - This is a boolean value that determines if child controls of the UpdatePanel are automatically considered triggers without having to be added to the Triggers collection.
Because your button is in a UserControl it won't be easy to add the control to the Triggers collection or to have the button call the Update method on the UpdatePanel that is not inside the UserControl.
Because your UpdatePanel contains the UserControl's your best bet is to enable ChildrenAsTriggers. If this doesn't work try setting the UpdateMode property to Always. If this still doesn't work then Phairoh is probably correct and your Button isn't posting back.
Sometimes solving this problem not really convenient with Triggers. So here is another fancy approach which could be used even from your user controls without any knowledge about Update Panel:
var scriptManager = ScriptManager.GetCurrent(Page);
if (scriptManager != null)
scriptManager.RegisterPostBackControl(SomeControlID);
Are you sure your buttons on your user control are attempting to do a postback? I haven't used update panels in a while (and I'd actually recommend avoiding them) but if I recall correctly they will refresh whenever a postback is done within them. This means that your buttons must be Asp:Buttons (or similar controls that cause postback) and not have some kind of javascript on them that would not allow their action to continue (such as a return false).
I have a ListView inside of an Update Panel and wanted to change the Select Query from the code behind fired by a button click event and then reload the ListView inside of the Update Panel. Does anyone know how to cause the Update Panel to refresh from the code behind?
Just do:
YourUpdatePanelId.Update();
From MSDN:
If the page is enabled for partial-page rendering, when you invoke the Update method, the UpdatePanel control's content is updated in the browser. Call the Update method if you have server code that must execute to determine whether an UpdatePanel control should be updated. If you plan to use the Update method, set the UpdateMode property to Conditional. If you want the decision to update the panel to be determined in server logic, make sure that the ChildrenAsTriggers property is false and that no explicit triggers are defined for the panel.
In a typical page development scenario, if you define triggers or if the ChildrenAsTriggers property is true for the UpdatePanel control, the Update method is automatically called during the page life cycle.
If the ContentTemplate property is not defined for the UpdatePanel control, no updates of the panel will occur.