Causing postback

I have written some javascript that async calls a webservice every second. If the service returns true, I want to cause a postback, with client script that can be handled on the server and tell a particular update panel to update in the server side handler.

I also wish to construct event arguments on the client to be passed as part of the post back.

How do I do this?

I need to do something similar, and I'm wondering if you could do it by having your page implement the IPostBackEventHandler. This interface requires that you implement a RaisePostBackEvent method. This method takes a string argument, and you could update your updatepanels in this method. Does anyone know if this approach would work?

Thanks,

Nick

hello.

ipostbackeventhandler is not the answer if you need to update updatepanels. what you could do is:

1. use the postbackaction

2. add a hidden dummy button to the updatepanel and force the submit by calling its click method

Nope, dont need to do that. ipostbackeventhandler is the way to go.

I add some javascript to the page via:

Microsoft.Web.UI.ScriptManager.RegisterClientScriptBlock(
this,
this.GetType(),
"UIService_Agent",
string.Format(
"function CheckAgentTimer()" +
"{{" +
"UIService.ShouldInteruptAgent(OnAgentTimerSucceeded,OnAgentTimerFailure);" +
"}}" +
"function OnAgentTimerSucceeded(result)" +
"{{" +
"if(eval(result))" +
"{{" +
"{0};" +
"}}" +
"setTimeout(\"CheckAgentTimer()\",{1});" +
"}}" +
"function OnAgentTimerFailure()" +
"{{" +
"setTimeout(\"CheckAgentTimer()\",60000);" +
"}}" +
"setTimeout(\"CheckAgentTimer()\",10000);",
this.Page.ClientScript.GetPostBackEventReference(this,AgentTasksTimer.AGENT_PROCESS),
this.timerInterval
),
true);

and then I implement the interface ipostbackeventhandler

public void RaisePostBackEvent(string eventArgument)
{
if (eventArgument == AGENT_PROCESS)
{
//Is There Work for the Agent?
if (WorkItemActionRequired != null && IsWorkItemActionRequired())
{
WorkItemActionRequired(this, new WorkItemEventArgs(ResourceReceiverService.GetUserWork(((IUserPrincipal)Context.User).Credentials.UserId, true)));
}
}
}

Messy I know, but bare with me...

You can then request that update panels are updated on the server i.e. myUpdatePanel.Update

This works!

Luis Abreu:

hello.

ipostbackeventhandler is not the answer if you need to update updatepanels. what you could do is:

1. use the postbackaction

2. add a hidden dummy button to the updatepanel and force the submit by calling its click method

How do you call the click method on a hidden dummy button?

hello.

you must get ?a refernce for the html control and call its click method:

$get("your_button_client_side_id").click();

But will this cause a partial or full post back?

Thanks,

Nick

hello.

it depend: if it's an asp.net button and it's placed inside an updatepanel (or if it's outside the updatepanel but it's configured as a trigger) you'll get a partial postback.

That might do the trick then. Right now I have implemented IPostBackHandler, but it causes a full post-back. I just want to do a partial. How do I make the button invisible, set Visible to false, or set visible to hidden in the button style?

Thanks,

Nick

hello.

it depend: if it's an asp.net button and it's placed inside an updatepanel (or if it's outside the updatepanel but it's configured as a trigger) you'll get a partial postback.
hello again.
well, i'd just add syle="display:none" in the asp.net button declaration.

This will also allow me to put code server-side?

Thanks,

Nick

Cause Postback with a Clientside Javascript

Hello,

I'm attempting to, with use of Clientside Javascripts (called from a Flash movie), to cause a Postback that will allow me to update the content of a GridView on my ASP.NET AJAX Page.

I've spend a lot of time looking at the documentation for the clientside framework, but I haven't been lucky enough to find anything. I realize that this poses the problem of a control having to cause a postback - but is there some way to do this (some workarround)?

Regards,
Jonas

Hi Jonas,

The way I do it (and I'm not sure it's a best practice / it is certainly a workaround ;) ) is the following:

To cause a postback: let the javascript find a button on the page (a server-side button) (for example: document.getElementById('MyButton')

Then you can touch the click event of that button

Make that click event cause a full postback or a partial postback (callback) if the button is a trigger of an updatepanel.

I hope all makes sence.
If you have further questions/remarks I'd like to hear them.

Greetz
Wim

HI Jonas,

You can write a javascript function withdocument.aspnetForm.submit(); statement in it and call it from your Flash. This will cause a postback and you can update the content.

A call to Sys.WebForms.PageRequestManager.getInstance()._doPostBack() is a good way to do it.

Cause a JavaScript Function to run after update (update panel postback)

Hello,

I ran into a problem that im not sure if the Atlas framework addresses.

I need to fire off a javascript function (which is decided server side)on a postback. To do this I am going to be using a hidden input field.(since I already have one on the form I use to send information forserver use.) From the server side, I can place the function names intothe hidden input field. But I can't cause them to run, on each postback.

I suppose that is confusing, let me try something simpler.

1. I fire off a postback in javascript - This is done using the__dopostback() and the server side fires off its if statements and doesits functions based on what has been placed into my hidden input field.(this is all good so far) (if I had to I could use the body's on formload ability to fire off the javascript functions I desire, but thatwont work for the next step, and is really ugly)

2. I include Atlas to make my postback not refresh the whole page. This is done by using UpdatePanels.

3. On the server side I need to somehow tell it to run certainjavascript functions when that postback finishes loading. (so like onpartial page load)

How do I do step 3?<script type="text/javascript">
function AfterPostback()
{
alert("This is where we check the hidden input and run the functions.");
}

function PageRequestManagerPropertyChanged(sender, args)
{
if (args.get_propertyName() == "inPostBack")
{
if (!$object("_PageRequestManager").get_inPostBack())
AfterPostback();
}
}

function pageLoad()
{
$object("_PageRequestManager").propertyChanged.add(PageRequestManagerPropertyChanged);
}
</script
<div>
<atlas:ScriptManagerEnablePartialRendering="true" ID="ScriptManager1" runat="server">
</atlas:ScriptManager>
<atlas:UpdatePanel runat="server" Mode="Conditional" ID="UpdatePanel1">
<ContentTemplate>
<%= DateTime.Now.ToLongTimeString() %>
</ContentTemplate>
<Triggers>
<atlas:ControlEventTrigger ControlID="UpdateTime" EventName="Click"/>
</Triggers>
</atlas:UpdatePanel>
<asp:Button ID="UpdateTime" runat="server" Text="Update Time" />
</div
Thats the solution I rigged up.
Hi,

Thanks for posting your solution. It works very well and solves a whole bunch of missing stuff with AtlasPanels. One problem dough. I had to move the call to JS function pageLoad() to the end of the html file part instead of putting it to body onload event.
Another option for doing this is theUpdateProgressSignup extension.