I have some controls within an UpdatePanel. Included are some buttons. How can I make these buttons so that they do a full postback rather than a partial AJAX postback?
Use a PostbackTrigger rather than an AsyncPostbackTrigger
Here's an example demonstrating how to use the PostbackTrigger instead of the AsyncPostbackTrigger:
ASPX Page:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Label ID="MyLabel" runat="server" />
<br/>
<asp:button ID="AjaxPostbackButton" Text="AJAX Postback" OnClick="AjaxPostbackButton_Click" runat="server" />
<asp:button ID="FullPostbackButton" Text="Full Postback" OnClick="FullPostbackButton_Click" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="AjaxPostbackButton" />
<asp:PostBackTrigger ControlID="FullPostbackButton" />
</Triggers>
</asp:UpdatePanel>
Code Behind:
private void AjaxPostbackButton_Click(object sender, EventArgs e)
{
MyLabel.Text = "Ajax Postback: " + DateTime.Now;
}
private void FullPostbackButton_Click(object sender, EventArgs e)
{
MyLabel.Text = "Full Postback: " + DateTime.Now;
}
Clicking on the "AJAX Postback" button will will update the panel using AJAX whereas the "Full Postback" button will reload the entire page.
Related
Using VS2012, I have a button that gets clicked to return some info to a textbox on the screen. I also have a label, label3, that is set to the following
protected void Page_Load(object sender, EventArgs e)
{
Label3.Text = ("THE FIRST RUN RECORDED AT" + DateTime.Now.ToString(" hh:mm:ss tt"));
}
Now naturally every time I press the button to return my information in the other part of the c#/web form it refreshes the hh:mm:ss to the current time.
My question is - Where I can call my function to stop my label from refreshing when the button is clicked?
The button calls this
protected void Button1_Click(object sender, EventArgs e)
{
WebService1 ws1 = new WebService1();
Label2.Text = ws1.codes(TextBox1.Text);
}
It just returns a string dependent on input.
Place Label3 out of UpdatePanel and other controls inside UpdatePanel.
In aspx :
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:Label ID="Label3" runat="server"></asp:Label>
<br />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<br />
<asp:Button ID="Button1" runat="server" onclick="Button1_Click2" Text="OK" />
<br />
<asp:Label ID="Label2" runat="server"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
I'm using this code in a page:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:Timer ID="timer" Interval="4000" runat="server" OnTick="timer_Tick" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Panel ID="pnlAlarm" runat="server" CssClass="pnlAlarm" ClientIDMode="Static">
<div id="Alarm">
<asp:Label ID="lblContent" runat="server" Text="Updating" CssClass="AlarmLogo"></asp:Label>
ClientIDMode="Static" />
</div>
</asp:Panel>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="timer" />
</Triggers>
</asp:UpdatePanel>
and in code behind I use this simple code:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Session["nima"] = 1;
}
}
protected void timer_Tick(object sender, EventArgs e)
{
int i = int.Parse(Session["nima"].ToString());
if (i==3)
{
lblContent.Text = i.ToString();
ScriptManager.RegisterStartupScript(this, GetType(), "AlarmMessage", "$('#pnlAlarm').slideToggle();", true);
Session["nima"] = 0;
}
else
{
i = i + 1;
Session["nima"] = i;
}
}
I want to know every time that I use RegisterStartupScript , $('#pnlAlarm').slideToggle(); add to my page and increase my page size?
thanlks
By definition, that method will:
register a startup script block that is included every time that an asynchronous postback occurs.
So yes, it will be included, and therefore increase your page size.
msdn ScriptManager.RegisterStartupScript Method
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" ChildrenAsTriggers="true"
runat="server">
<ContentTemplate>
<asp:ImageButton ID="imagebutton1" runat="server" ImageUrl="~/image.jpg" Width="125"
Height="125" onclick="imagebutton1_Click" />
<asp:Timer ID="timer1" runat="server" Interval="10000" ontick="timer1_Tick" />
<asp:Label ID="label1" Visible="false" runat="server" Text="" />
</ContentTemplate>
</asp:UpdatePanel>
If I don't use an update panel the whole page refreshes.
protected void imagebutton1_Click(object sender, ImageClickEventArgs e){
string link = label1.Text;
Page.ClientScript.RegisterStartupScript(this.GetType(), "OPEN", "window.open(" + link +
",'mywindow','width=200,height=200,');", true);
}
This is the variable "link" here in the timer handler
Random r = new Random();
if (datatable1.Rows.Count > 0)
{
int randomnumber = r.Next(0, i);
DataRow datarow1= datatable1.Rows[randomnumber ];
imagebutton1.ImageUrl = (String)datarow1["image"];
imagebutton1.DataBind();
label1.Text = (String)datarow1["Link"];
}
I had to just add postback triggers as shown below in the updatepanel to make it work.
<Triggers>
<asp:PostBackTrigger ControlID="ImageButton"/>
</Triggers>
It's hard to say since you didn't really include a question, but if you want a piece of client side code to run when an UpdatePanel refreshes, use the client side pageLoad() method.
Also, you are using a server side event to do a client side operation. Use the OnClientClick handler instead:
<asp:ImageButton ID="imagebutton1" runat="server" ImageUrl="~/image.jpg" Width="125"
Height="125" OnClienClick="return openPopUp(this.href);" />
function openPopUp(link)
{
window.open(this.href,'mywindow','width=200,height=200,');
return false;
}
Try changing to UpdateMode="Always"
This is my situation:
Page:
<asp:UpdatePanel ID="updatePanel1" runat="server" ChildrenAsTriggers="true">
<ContentTemplate>
...
<uc:ChildControl ID="ucChild" runat="server" />
...
</ContentTemplate>
</asp:UpdatePanel>
ChildControl:
...
<asp:DropDownList id="dropDown1" runat="server" />
...
I want to update the UpdatePanel (asynchronously) in the Page when the selection of the DropDownList in the ChildControl changes. I tried AutoPostBack="true", but this always leads to a full PostBack of the Page (see this question).
I tried to use
<Triggers>
<asp:AsyncPostBackTrigger ControlID="???" EventName="SelectedIndexChanged" />
</Triggers>
but neither "dropDown1" nor "ucChild.dropDown1" worked as values for ControlID.
I also tried to pass a reference of the UpdatePanel to the ChildControl and add a Trigger in the following way:
protected override void OnPreRender(EventArgs e)
{
if (ParentUpdatePanel != null)
{
AsyncPostBackTrigger trigger = new AsyncPostBackTrigger();
trigger.ControlID = dropDown1.ID;
trigger.EventName = "SelectedIndexChanged";
ParentUpdatePanel.Triggers.Add(trigger);
}
base.OnPreRender(e);
}
(also tried with dropDown1.ChildID)
But I am still unable to get the UpdatePanel to trigger when the value in the Dropdown changes. The problem seems to be that the UpdatePanel cannot see the Control in the ChildControl and therefore is unable to set the Trigger accordingly.
How can I do it?
Maybe with a trick putting this code on dropdown list.
dropDown1.Attributes["onchange"] =
Page.ClientScript.GetPostBackEventReference(ParentUpdatePanel, "") + "; return false;";
When you change the drop down list you send an update event to UpdatePanel using direct javascript call.
Setting AutoPostBack=True on the Drop Down List control should not refresh the entire page if it is in an update panel.
I created a simple example:
default.aspx:
<form id="form1" runat="server">
<div>
<asp:ScriptManager runat="server"></asp:ScriptManager>
<asp:UpdatePanel ID="up" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional">
<ContentTemplate>
<uc:UserControl ID="ucChild" runat="Server"></uc:UserControl>
<asp:Label ID="lbl" runat="server"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
default.aspx.cs (code behind):
public partial class _default : System.Web.UI.Page {
protected void Page_Load(object sender, EventArgs e) {
lbl.Text = ucChild.value;
}
}
UserControl.ascx:
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="UserControl.ascx.cs" Inherits="somenamespace.UserControl" %>
<asp:DropDownList runat="server" ID="ddl" AutoPostBack="true">
<asp:ListItem Text="1" Value="1"></asp:ListItem>
<asp:ListItem Text="2" Value="2"></asp:ListItem>
</asp:DropDownList>
UserControl.ascx.cs (code behind):
public partial class UserControl : System.Web.UI.UserControl {
public string value {
get { return ddl.SelectedValue.ToString(); }
}
}
When I change the dropdownlist, the label is updated without a full post back.
I have the following UpdatePanel that gets an image from an ashx handler all of which works fine when the page is refreshed. However, when the timer fires, the label is refreshed with current time, but never the image.
<asp:UpdatePanel runat="server" id="TimedPanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:Image ID="Image1" runat="server" Height="218px"
ImageUrl="~/getImage.ashx?cam=1" Width="303px" BorderWidth="10px" />
<asp:Timer ID="UpdateTimer" runat="server" interval="1250"
ontick="UpdateTimer_Tick" />
<asp:Label ID="DateStampLabel" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger controlid="UpdateTimer" eventname="Tick" />
</Triggers>
</asp:UpdatePanel>
The timer routine is:
protected void UpdateTimer_Tick(object sender, EventArgs e)
{
DateStampLabel.Text = DateTime.Now.ToString();
}
Why isn't the image refreshed?
AJAX in general is really prone to browser caching. I normally add a DateTime.Now.Ticks to the URL. Also, your UpdateMode is Conditional, you have to call Update():
protected void UpdateTimer_Tick(object sender, EventArgs e)
{
DateStampLabel.Text = DateTime.Now.ToString();
Image1.ImageUrl += "&CacheBuster=" + DateTime.Now.Ticks.ToString();
TimedPanel.Update();
}