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dropdown onselectedindexchanged event not firing and value kept on postback c#

I can't get the dropdown onselectedindexchanged event to fire, and when I make a selection it resets the value of the dropdown onpostback, even though I have the if (!ispostback) in the page load event.
this is a content page in a master page in asp in case that matters.
<asp:UpdatePanel runat="server">
<ContentTemplate>
<asp:DropDownList ID="EventSVCProgList" runat="server"
EnableViewState="true"
OnSelectedIndexChanged="EventSVCProgList_SelectedIndexChanged"
AutoPostBack="true"></asp:DropDownList>
</ContentTemplate>
</asp:UpdatePanel>
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
SqlConnection constr = new SqlConnection(ConfigurationManager.ConnectionStrings["CBTestDBConnectionString"].ConnectionString);
SqlCommand eventsvcprogCMD = new SqlCommand("select*from SvcProg where eventatteligable=1", constr); // table name
SqlDataAdapter eventsvcadapt = new SqlDataAdapter(eventsvcprogCMD);
DataSet eventsvcset = new DataSet();
constr.Open();
eventsvcadapt.Fill(eventsvcset); // fill dataset
EventSVCProgList.DataTextField = eventsvcset.Tables[0].Columns["SvcProgID"].ToString(); // text field name of table dispalyed in dropdown
EventSVCProgList.DataValueField = eventsvcset.Tables[0].Columns["eventatteligable"].ToString();
EventSVCProgList.DataSource = eventsvcset.Tables[0]; //assigning datasource to the dropdownlist
EventSVCProgList.DataBind(); //binding dropdownlist
constr.Close();
}
}
protected void EventSVCProgList_SelectedIndexChanged(object sender, EventArgs e)
{
MessageBox.Show("Eat Poop");
var somevalue = EventSVCProgList.SelectedValue;
}

There are couple of things.
1) You need to add a Script Manager to the page at the top if not added already(it will give you a runtime error if you have not added a script Manager to the page)
2) You need to change the Update Panel content as shown below
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:DropDownList ID="EventSVCProgList" runat="server" AutoPostBack="True" OnSelectedIndexChanged="EventSVCProgList_SelectedIndexChanged">
</asp:DropDownList>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="EventSVCProgList" EventName="SelectedIndexChanged" />
</Triggers>
</asp:UpdatePanel>

There seems that any parent control or page leven ViewState is disabled. please check in debug mode that what value you getting for EventSVCProgList.EnableViewState and other parent controls' as well.

thanks for the help. its still not working so i'm just going to try to use javascript instead. its got to be some fundamental flaw with the way the master page or content page is setup.

Unable to retrieve DDL SelectedValue bound in ASPX after Page Load

I have the following markup / code block in the ASPX file.
The binding of the ddl is triggered after Page_Load event which is in the code behind file.
This results me not able to get the selected value of the dropdownlist if I were to use such flow.
However for some purpose I require it to work this way.
Any idea how I could get the dropdownlist selected value when a post back is being triggered (click of the button)?
Page URL: page.aspx?para1=0&para2=value
ASPX PAGE
<%
if (Convert.ToInt32(Request.QueryString["para1"]) == 0)
{
ddl.DataValueField = "value";
ddl.DataTextField = "text";
ddl.DataSource = ds; //ds is valid, exact code not shown
ddl.DataBind();
} else {
//write in this area
Response.Write("Not 0");
}
%>
<form runat="server" id="user_form" class="form-horizontal">
<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server">
</asp:ToolkitScriptManager>
<asp:UpdatePanel ID="updPanel" runat="server">
<ContentTemplate>
<asp:DropDownList runat="server" ID="ddl">
</asp:DropDownList>
<%-- this button will call btnSave_Click to get the ddl's value--%>
<asp:Button runat="server" ID="btn" Text="Button" OnClick="btn_Click" />
</ContentTemplate>
</asp:UpdatePanel>
</form>
CODE BEHIND
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
//do my stuff
}
}
protected void btn_Click(object sender, EventArgs e)
{
int intValue = Convert.ToInt32(ddl.SelectedValue);
//do my stuff
}
The ASPX Page code block will run after Page_Load / page's lifecycle, then will determine what to do base on the url parameters.
Thanks in advance!

You could always throw in a hidden object and use jquery to copy the value to the hidden value based on a certain action without a postback and would do it client side like it sounds like you want it to do

How to re-bind ListView on OnClick event of a button?

this seemed simple at first but I can't get it to work.
I have the following scenario:
<asp:ListView ID="CommentsListView" runat="server">
<LayoutTemplate>
<asp:PlaceHolder ID="itemPlaceholder" runat="server" />
</LayoutTemplate>
<ItemTemplate>
<UC:Comment runat="server" CommentItem="<%# CurrentComment %>" />
<br />
</ItemTemplate>
</asp:ListView>
<asp:TextBox ID="NewComment" runat="server" />
<asp:ImageButton ImageUrl="/images/ball.png" runat="server"
OnClick="SubmitComment" />
Code:
protected void Page_Load(object sender, EventArgs e)
{
RenderListView();
}
protected void RenderListView()
{
CommentsListView.DataSource = //Get the data source objects
CommentsListView.DataBind();
}
protected CommentObject CurrentComment
{
get { return (CommentObject)Page.GetDataItem(); }
}
protected void SubmitComment(object sender, ImageClickEventArgs e)
{
//code to submit comment
RenderListView();
}
basically, when I submit a comment, I want to see it in the ListView, but I don't. "MyControl" gets a null comment in the post-back, for all of the items (not just the new one).
Only after I refresh the page, I can see the new comment that I'v submitted. I can't however refresh the page every submit because this code is inside an UpdatePanel (the issue occurs without the UpdatePanel as well).
Any idea how to solve this?

I can't find any specifics on this, but I have a hunch the user control in your ItemTemplate is causing the issue. Can you remove it and see if it works?

I notice that you are calling RenderListView in both SubmitComment and PageLoad which I believe will cause it to fire twice when the button is clicked (with PageLoad firing first). It looks like the code you posted is simplified. Is it possible that there is something happening in the PageLoad which is sabotaging your SubmitComment steps?

I finally solved it, if anyone else may encounter this -
The solution was to avoid "<%#" and instead use the ItemDataBound event:
<asp:ListView ID="Comments" runat="server"
OnItemDataBound="CommentsItemDataBound">
and the method itself:
protected void CommentsItemDataBound(object sender, ListViewItemEventArgs e)
{
var commentItem = (Comment)(((ListViewDataItem)e.Item).DataItem);
var commentControl = (Comment)e.Item.FindControl("CommentControl");
commentControl.CommentItem = commentItem;
}
This way, the binding of each control works as expected.

how to make a Image-button in the user control execute code in the defaultpage.aspx?

1-I have three user controls.
2-I added them to AJAX TabContainer on my default.aspx page
<asp:TabContainer ID="TabContainer1" runat="server">
<asp:TabPanel runat="server" ID="GroupOne">
<HeaderTemplate>
1
</HeaderTemplate>
<ContentTemplate>
<SUR:GroupOne ID="group1" runat="server" />
</ContentTemplate>
</asp:TabPanel>
<asp:TabPanel ID="GroupTwo" runat="server">
<HeaderTemplate>
2
</HeaderTemplate>
<ContentTemplate>
<SUR:GroupTwo is="group2" runat="server" />
</ContentTemplate>
</asp:TabPanel>
<asp:TabPanel ID="GroupThree" runat="server">
<HeaderTemplate>
3
</HeaderTemplate>
<ContentTemplate>
<SUR:GroupThree ID="grup3" runat="server" />
</ContentTemplate>
</asp:TabPanel>
</asp:TabContainer>
3- in the first user control i have image-button
<asp:ImageButton ID="ImageButton1" runat="server" />
4- I have this code in my default.vb
Public Sub movit()
GroupThree.Enabled = True
TabContainer1.ActiveTab = GroupThree
End Sub
so how can i execute that sub when i click on the image button in the user-control??

I believe you need to use a delegate to achive this. You can try followings
In your ascx.cs or vb file Add a delegate inside the namespace but outside the UserControl class.
public delegate void ImageButtonClickEventHandler(Object sender, EventArgs args);
Inside UserControl class add an event using delegate.After that call the delegate inside ImageButtonClick event.
public event ImageButtonClickEventHandler ImageButtonClickEvent;
private void imageButton_Click(object sender, System.EventArgs e)
{
if(ImageButtonClickEvent!= null)
{
ImageButtonClickEvent(sender,e);
}
}
In your aspx page add this inside page load event.
UserControl1.ImageButtonClickEvent+=new ImageButtonClickEventHandler(UserControl1_ImageButtonClickEvent);
Finally declare UserControl1_ImageButtonClickEvent function
private void UserControl1_ImageButtonClickEvent(Object sender, EventArgs args)
{
//Call your methods
}

From your designer, double-click the button, this will wire up an event-handler (ImageButton1_Click) and set the onclick property of your imagebutton to ImageButton1_Click.
In the code behind of your page, just call movit() from the generated eventhandler.
[Edit]
Didn't see that the image button was in a user control.
The way to go would be to add an Event to your user control. Raise it when the user clicks the imagebutton. In the page, handle the new event of the user control and call the movit() function.

What aboiut..
1) add an event handler to the user control
public event EventHandler Click
{
add
{
ImageButton1.Click += value;
}
remove
{
ImageButton1.Click -= value;
}
}
2) subscribe to this event from the page you are using the control - default.aspx
<user:control runat="server" ID="uc" OnClick="uc_OnClick" />
and
protected void uc_OnClick(object sender, EventArgs e)
{
movit();
}

TextChanged event triggering again when I make a postback

<asp:UpdatePanel ID="uppBaixa" runat="server">
<ContentTemplate>
<asp:TextBox ID="txt1" runat="server" AutoPostBack="true" OnTextChanged="txt1_TextChanged"></asp:TextBox>
<asp:TextBox ID="txt2" runat="server"></asp:TextBox>
<asp:Button ID="btnSave" runat="server" OnClick="btnSave_Click" />
</ContentTemplate>
</asp:UpdatePanel>
This is basically what the ASPX looks like. When I leave (tab) txt1 the TextChanged event is called and it normally fills txt2. But when I change the text in txt2and hit btnSaveto update this data, the txt1_TextChanged is called AGAIN (before the actual btnSave_Click method triggers)

If you
Take your sample UpdatePanel and put it into a new project (and add the ScriptManager)
Add the following methods
protected void btnSave_Click(object sender, EventArgs e)
{
this.txt1.Text = "foo";
}
protected void txt1_TextChanged(object sender, EventArgs e)
{
txt2.Text = txt1.Text;
}
Update txt1 to ABC then txt2 will become ABC
Update txt2 to Bar then txt1.Text will be ABC and txt2 will Bar
Pressing Save will just change txt1 to Foo and txt will remain Bar
This means that what you've described doesn't reproduce.
Note that even when you set txt1.text = "foo" on server side it doesn't raise the textChanged event, which means its probably something on the client side
Try adding this to your Page_Load event to find it.
this.btnSave.Attributes.Add("OnClick", "debugger");