User control - calling a vb linkbutton's(withi

问题:

how can i call a VB function - deleteevent() in usercontrol.ascx.vb from a javascript function in clickhandler(e) in usercontrol.ascx. The call should cause a postback because I need the usercontrol to display the changes.

I am currently trying to do it by using a linkbutton with style display:none, and calling its click event from the javascript function. But i dunno how to call the click event.

I had to pass a value to the vb function from the javascript, but i am taking care of it using a hiddenfield.

the environment is asp.net 3.0 language:vb

Thanks.

回答1:

Check this two links about calling codebehind methods with JQuery :

Using jQuery to directly call ASP.NET AJAX page methods

Using jQuery to Call ASP.NET AJAX Page Methods

You should call aspx instead of ascx methods. beacuse at runtime all user controls (ascx) merged to your page (aspx).

If you have a user control with multiple instances in a page, you should use a parameter to define context of method in each usercontrol. Maybe user control's clientID.

回答2:

This one is slightly tricky, but kinda fun.

Basically, you need to:

1. Implement IPostBackEventHandler on the control where you want to raise the event
2. Create a postback reference for the control
3. Call the postback reference, either via a hyperlink or jscript

4. In the code behind, handle the postback reference and call your code

   Public Class MyControl
   Inherits UserControl
   Implements IPostBackEventHandler
   
   Public Sub RaisePostBackEvent(ByVal eventArgument As String) Implements System.Web.UI.IPostBackEventHandler.RaisePostBackEvent
   
       ' Call deleteEvent here
       DeleteEvent(eventArgument)  ' This will contain "SomeArgumentYouWantToPassToDeleteEvent"
   
   End Sub
   
   Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
       Dim cs As ClientScriptManager = Page.ClientScript
   
       Dim a As New HtmlAnchor()
       a.ID = "myanchor1"
       a.InnerText = "Delete Event"
       a.HRef = cs.GetPostBackClientHyperlink(Me, "SomeArgumentYouWantToPassToDeleteEvent")
   
       ' You could alternatively construct some jscript and output it.
   
       Controls.Add(a)
   
   End Sub
   End Class
   

For more info, see here: ClientScriptManager.GetPostBackEventReference