FileUpload in FormView inside an UpdatePanel - asp.net

The Scenario:
I have an ASP.Net webpage which I intend to use for letting the user(not the real users, but content manager basically) insert and edit the records in a table using a FormView. This FormView is inside an UpdatePanel, as I'm also using cascading dropdownlists to let the user select some values.
Now, this FormView also contains 4 FileUpload controls, and as you might know that these fileupload controls require a full postback since most browsers do not let Javascript access the disk. So, this problem would have been solved by doing something like:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:PostBackTrigger ControlID="InsertButton" />
<asp:PostBackTrigger ControlID="UpdateButton" />
</Triggers>
<ContentTemplate>....</ContentTemplate>
</asp:UpdatePanel>
Edit: Forgot to add that the fileuploading takes place in the OnUpdating and OnInserting events of the SqlDataSource.
The Problem:
Since the InsertButton and the UpdateButton reside inside the Formview, I cannot directly access their ID's through markup. And MSDN says that:
Programmatically adding
PostBackTrigger controls is not
supported.
Please suggest some solution to make this work. Any insight on the matter is highly appreciated. Thanks.
P.S.- A workable solution for me was to set the UpdatePanel's PostBackTrigger as the whole FormView itself:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:PostBackTrigger ControlID="FormView1" />
</Triggers>
<ContentTemplate>....</ContentTemplate>
</asp:UpdatePanel>
But now due to a bit of change in requirements, this solution(if you call it a solution) is not acceptable.

Have you given a though about using Iframe for doing the postback ? something like:
<iframe name="uploader" id=uploader
src="uploaderSender.aspx?AllowedExtension=<%= AllowedExtension %>&StoringPath=<%= StoringPath %>&StoringFileName=<%= StoringFileName %>&OldFileName=<%= OldFileName %>&MaximumSize=<%= MaximumSize %>"
width="450" height="50" frameborder=0 scrolling=no >
</iframe>
with uploaderSender.aspx like :
<form action="UploaderReceiver.aspx" method="post" enctype="multipart/form-data">
<input type="file" name="file" id="file" onchange="document.getElementById('IsFileUploading').style.visibility = 'visible'; document.forms[0].submit()"/>
<span id="IsFileUploading" style="visibility: hidden">
<asp:Image ID="Image1" runat="server" ImageUrl="~/immagini/Ajax-loader.gif" />
</span>
</form>
and UploaderReceiver.aspx like :
protected void Page_Load(object sender, EventArgs e)
{
//if there is one file to process
if (Request.Files.Count > 0)
//create the folder if it does'nt exists and returns the local path to get it
string StoringPathToBeSaved = StoringPath.GetFolderPath();
// append the name of the file to upload to the path.
StoringPathToBeSaved = StoringPathToBeSaved + StoringFileName + Extension;
Request.Files[0].SaveAs(StoringPathToBeSaved);
}
this is just bits of code just for you to figure out if you would be interested in this way of dealing with the upload, I can give you more if you want after.
see you, and good luck with your code,

Yay!! Finally got it to work!
Here's How:
Well contrary to what MSDN says, we can in fact add PostBack Triggers Programmatically. Not necessarily to the UpdatePanel, but to the ScriptManager.
After hours of playing around, here's what worked:
We are not able to access controls inside a FormView, untill the template has been rendered, so we can only add postback triggers after the formview's OnDataBound Event.
protected void FormView1_DataBound(object sender, EventArgs e)
{
if (FormView1.CurrentMode == FormViewMode.Edit)
{
LinkButton lb = (LinkButton)FormView1.FindControl("UpdateButton");
ScriptManager.GetCurrent(Page).RegisterPostBackControl(lb);
}
//Similarily you can put register the Insert LinkButton as well.
}
And now, if your UpdatePanel causes ConditionalUpdate, you can do something like this to make it work:
The Markup:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>..
<EditItemTemplate>
...
<asp:LinkButton ID="UpdateButton" runat="server" CausesValidation="True" OnClick="Cause_PostBack"CommandName="Update">Update</asp:LinkButton>
...
</EditItemTemplate>
..</ContentTemplate>
</asp:UpdatePanel>
CodeBehind:
//call this function as the OnClick Event Handler for the Controls you want to register as
//triggers.
protected void Cause_PostBack()
{
UpdatePanel1.Update();
}
Otherwise, if your situation allows it(as mine does), just set the UpdatePanel's UpdateMode="Always"

This is old, but was trying to solve another problem and ran into this. This wasn't my problem, but here's an alternative for anyone new who runs into this as well.
You stated your problem as:
Since the InsertButton and the UpdateButton reside inside the Formview, I cannot directly access their ID's through markup
You actually can access their ID's through markup to use as the ControlID in the PostBackTrigger. You just have to use the button's name that is created in the page html mark-up as the ControlID. You can find the name created by viewing the page source when you're viewing the page in the browser. It typically is the name of the FormView + $ + name of the button.
For example, let's say you have a FormView named "FormView1" that contains an Insert button which you gave the ID of "btnInsert" during design. If you open up your page in the browser to view it live and then view the page's source, you'll notice that the html mark-up of the button will actually be given the name "FormView1$btnInsert".
Use that name as the ControlID in your PostBackTrigger and your update panel will work.
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:PostBackTrigger ControlID="FormView1$btnInsert" />
</Triggers>
<ContentTemplate>....</ContentTemplate>
</asp:UpdatePanel>

Related

Cannot Download file in UpdatePanel

The below code works which allows me to download a Word document.....
Try
Response.BufferOutput = True
HttpContext.Current.Response.Clear()
HttpContext.Current.Response.Charset = ""
HttpContext.Current.Response.ContentType = "application/msword"
HttpContext.Current.Response.AddHeader("Content-Disposition", "inline;filename=myfile.doc")
HttpContext.Current.Response.Write(s)
'HttpContext.Current.Response.End()
HttpContext.Current.ApplicationInstance.CompleteRequest()
HttpContext.Current.Response.Flush()
Catch ex As Exception
Response.Write(ex.Message)
End Try
But as soon as i add an UpdatePanel - it doesnt download the file and no errors are generated? After reading around i added a trigger with the ControlID value set to the button that starts creating the Word doc file. I've tried several combinations of code but nothing seems to work. Any help on how to narrow this down? I've also debugged and no errors show. Ive checked my downloads folder - nothing there, tried setting no cache (Response.Cache.SetCacheability(HttpCacheability.NoCache)) and that didnt work. As soon as i remove the UpdatePanel then all seems to work?
<asp:UpdateProgress ID="ProgressUpdate" AssociatedUpdatePanelID="UpdatePanel1" runat="server">
<ProgressTemplate>
<img alt="progress" src="../images/loading.gif" />
</ProgressTemplate>
</asp:UpdateProgress>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:PostBackTrigger ControlID="buttonDownloadFile" />
</Triggers>
<ContentTemplate>
..
Completely lost on this one. Could anyone suggest a workaround or how to tackle this problem?
The accepted answer is just plain wrong. You need to register the control with the scriptmanager. Mine is in the master page and here is the code i use to register any button for proper post backs.
private void MasterPageRegisterButtonForPostBack(Control bt)
{
MasterPage masterPage = Master;
if (masterPage is MainMaster)
{
var mainMaster = masterPage as MainMaster;
if (bt != null && mainMaster.MasterScriptManager != null)
{
mainMaster.MasterScriptManager.RegisterPostBackControl(bt);
}
}
}
I got it working the following way:
inside my Update Panel I configured the controls that may forece a full postback in order to get the download working.
(I'm using also Master pages,this is the same solution as Steve's but registering it in the aspx and not in code behind)
<asp:UpdatePanel runat="server" ID="UpdatePanelDownload" UpdateMode="Conditional" ChildrenAsTriggers="True">
<ContentTemplate>
<asp:LinkButton ID="LinkButtonDownload" OnClick="Download_Click" runat="Server">Save XML</asp:LinkButton>
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="LinkButtonDownlod" />
</Triggers>
</asp:UpdatePanel>
I had to open an ashx Generic Handler in another window and passed some session variables to it, like filename, full path, etc.
I did it like this
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<%foreach(var f in listOfObject){ %>
<a class="btn btn-danger" href="javascript:__doPostBack('ctl00$BodyContent$butDownload', '<%=f.ID %>')" >Download</a>
<%} %>
</ContentTemplate>
</asp:UpdatePanel>
<asp:LinkButton runat="server" ID="butDownload" OnClick="butDownload_Click" style="display:none;">LinkButton</asp:LinkButton>
///----Server-Side-----
protected void butDownload_Click(object sender, EventArgs e)
{
string strID = Request["__EVENTARGUMENT"];
if (!string.IsNullOrEmpty(strID))
{
int id = int.Parse(strID);
//---Do what you want here
}
}
The UpdatePanel does not support file upload or download. There are tons of ajax-enabled components out there that will do this, Google is your friend.
EDIT: -
Some examples: -
http://forums.asp.net/t/1076322.aspx?How+to+create+a+flipcart+like+panel+for+showing+products+in+gridview - I like this approach, he injects an IFrame using JavaScript that points to a page responsible for downloading the file. Works inside an UpdatePanel
http://encosia.com/ajax-file-downloads-and-iframes/ - Similar approach

asp.net set textbox control in panel contol

I want to set the textbox contol located in the panel control via code
I know to retrieve the inputted value in the textbox control:
string myVal = Request.Form["txtResult"];
I want to set the txtResult.text = "some text";
makeup snippet:
<asp:Panel ID="Panel1" runat="server" Style="display: none" Width="233px">
<asp:TextBox ID="txtResult" runat="server" AutoPostBack="True"></asp:TextBox>
<br />
<div align="center">
<asp:Button ID="OkButton" runat="server" Text="OK" />
<asp:Button ID="CancelButton" runat="server" Text="Cancel" />
</div>
</asp:Panel>
txtResult is not available within code, I tried to see if it is available in the page_load, it's not
texReults was a typo, its txtResult, I updated the ID
the intellisense does not recognize any cntr by the name txtResult
its a new web application and the panel visibility=True
maybee this wil help, above the snipet, I use ScriptManager from the AJAX Exstension
I am aware of he Asnchronius affects, partial potback, etc.
It's a managed control, you should be able to set it on the Page_Load event:
protected void Page_Load(object sender, System.EventArgs e)
{
txtResult.Text = "some text";
}
Update: Based on your update, there are a couple of things that you would need to check:
Spelling: Are you sure you're spelling the control name correctly?
Its ID in your code is "txtResults", but you're referencing it as
"txtResult".
Designer: Did you copy the aspx page or bypass VS in some way for this page? If so check the .designer file for the reference to the control: i.e. "Page1.aspx.designer.cs"
Visibility: Is the Panel control's visibility set to true? If not, then it won't render the controls that are contained within it.
Update 2: If you're doing this through scriptmanager, then I highly recommend that you read through this: http://www.wrox.com/WileyCDA/Section/Using-the-ASP-NET-AJAX-ScriptManager.id-305492.html

How to refresh an opened popup extender panel

I have a gridview where I have button for each row. After clicking this button, the Modal PopUp Extender Panel is opened (with PanelName.Show()). The Panel contains a user control, which shows some labels, textboxes,etc. with an additional info binded form SqlDataSource. Until this point it works well. But, when I click another button, the panel is purely shown but the content is not refreshed (based on which button is clicked, some details info should be shown). Basically, the method SqlDataSource_Selecting is called only for the panel popup showing but not anymore.
How can I force panel to be refreshed (reloaded) after each PanelName.Show()??
Thanks in advance.
If I'm understanding your question correctly, I think the problem is that you just need to re-Bind your data bound controls after the user clicks the button to change the Selected item. You can use [ControlName].DataBind() to do that. Does that make sense?
It depends on whether the control(s) you want to refresh are DataBound() or not.
In other words, can you force the control to reload by using a DataBind() method call to force the control to reload itself, with either the same or new data?
Most GUI controls have the DataBind() method, but it's useless if the control is not actually using data to work!
This is why in your case your panel is not "refreshed" with new data because using a DataBind() on the panel does nothing. Using a databind() on the entire GridView is a different story and should work. Maybe place an UPDATEPANEL around the whole lot? If you do you have to be careful your normal edits and other Commands on the rows will continue to work.
However, What you can do is place the modalpopupextender inside your TemplateField, and using a "trick", you can keep your server post backs and still fire the popup panel.
ie
<asp:UpdatePanel ID="upADDMAIN" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Button ID="btnADD" runat="server" Text="NEW LOGIN" BackColor="Blue" Font-Bold="True" ForeColor="#FFFFCC" OnClick="btnADD_Click" />
<asp:Button ID="btnDUM" runat="server" style="display:none" />
<div style="height:20px">
</div>
<ajaxToolkit:ModalPopupExtender ID="mpeADD" runat="server"
targetcontrolid="btnDUM"
popupcontrolid="upADD"
backgroundcssclass="modelbackground">
</ajaxToolkit:ModalPopupExtender>
<asp:UpdatePanel ID="upAdd" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Panel ID="pnlADD" runat="server" Width="700px" HorizontalAlign="Center" CssClass="auto-style10" Height="200px">
..
..
<div id="puFTR" class="auto-style17" style="vertical-align: middle">
<asp:Button id="btnOK" runat="server" Text="OK" style="width: 80px" OnClick="btnOK_Click" />
<asp:Button id="btnCAN" runat="server" Text="CANCEL" style="width: 80px" OnClick="btnCAN_Click" CausesValidation="False" />
</div>
</asp:Panel>
</ContentTemplate>
</asp:UpdatePanel>
</ContentTemplate>
</asp:UpdatePanel>
As you may see, the btnDUM control is a Dummy to get the MPE to work, but it's not actually used as it's hidden by the style="display:none" tag.
However, the btnADD does work because it calls a Click() method on the server side which does the refresh of data on your new row. You may have to use a little jScript to pass the ROWINDEX into the Click() method for it to work with a GridView.
Incidentally, the Click() method in my case "controls" the MPE manually...
protected void btnADD_Click(object sender, EventArgs e)
{
ClearADDform();
mpeADD.Show();
}
protected void ClearADDform()
{
txtLOGIN.Text = string.Empty;
cbISActive.Checked = true;
txtPWD.Text = string.Empty;
ddlAgent.SelectedIndex = -1;
}
In my case, the above code example is outside a GridView, so you'll need to adjust.
But the point is, you can still have Server Side calls using Ajax popups!
Good luck.

DropDownList's SelectedIndexChanged event not firing

I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the SelectedIndexChanged event.
First, the actual object's HTML code:
<asp:DropDownList ID="logList" runat="server"
onselectedindexchanged="itemSelected">
</asp:DropDownList>
And this is that function, itemSelected:
protected void itemSelected(object sender, EventArgs e)
{
Response.Write("Getting clicked; " + sender.GetType().ToString());
FileInfo selectedfile;
Response.Write("<script>alert('Hello')</script>");
foreach (FileInfo file in logs)
{
if (file.Name == logList.Items[logList.SelectedIndex].Text)
{
Response.Write("<script>alert('Hello')</script>");
}
}
}
None of the Responses appear, and that portion of JavaScript is never run. I've tried this on the latest 3.6 version of Firefox, as well as Internet Explorer 8. This is being served from a Windows Server 2003 R2 machine, running ASP.NET with the .NET Framework version 4.
Set DropDownList AutoPostBack property to true.
Eg:
<asp:DropDownList ID="logList" runat="server" AutoPostBack="True"
onselectedindexchanged="itemSelected">
</asp:DropDownList>
try setting AutoPostBack="True" on the DropDownList.
I know its bit older post, but still i would like to add up something to the answers above.
There might be some situation where in, the "value" of more than one items in the dropdown list is duplicated/same. So, make sure that you have no repeated values in the list items to trigger this "onselectedindexchanged" event
Add property ViewStateMode="Enabled" and EnableViewState="true"
And AutoPostBack="true" in drop DropDownList
Also make sure the page is valid.
You can check this in the browsers developer tools (F12)
In the Console tab select the correct Target/Frame and check for the [Page_IsValid] property
If the page is not valid the form will not submit and therefore not fire the event.
For me answer was aspx page attribute, i added Async="true" to page attributes and this solved my problem.
<%# Page Language="C#" MasterPageFile="~/MasterPage/Reports.Master".....
AutoEventWireup="true" Async="true" %>
This is the structure of my update panel
<div>
<asp:UpdatePanel ID="updt" runat="server">
<ContentTemplate>
<asp:DropDownList ID="id" runat="server" AutoPostBack="true" onselectedindexchanged="your server side function" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
Instead of what you have written, you can write it directly in the SelectedIndexChanged event of the dropdownlist control, e.g.
protected void ddlleavetype_SelectedIndexChanged(object sender, EventArgs e)
{
//code goes here
}

Why aren't all controls initialised at the event handling point of the ASP.NET page lifecycle?

I have a user control embedded in a web part. It has the following snippets of code:
protected TextBox searchTextBox;
protected Button goButton;
protected Button nextButton;
protected Repeater pushpins;
protected Label currentPageLabel;
protected void goButton_Click(object sender, EventArgs e)
{
// Do stuff
}
<asp:TextBox ID="searchTextBox" runat="server" />
<asp:Button ID="goButton" runat="server" Text="Go" OnClick="goButton_Click" />
<asp:Repeater ID="pushpins" runat="server" EnableViewState="false">
<ItemTemplate>Blah</ItemTemplate>
</asp:Repeater>
<asp:Label ID="currentPageLabel" runat="server" />
<asp:Button ID="nextButton" runat="server" Text=" >> " OnClick="nextButton_Click" />
(There is no OnLoad or CreateChildControls method.)
If I place a breakpoint on the first line of goButton_Click, I find:
searchTextBox: initialised
goButton: initialised
nextButton: NULL
pushpins: initialised
currentPageLabel: NULL
Why are some controls initialised and others not? How do I get around this if I'd like to update the Text property on currentPageLabel?
Update:
I've placed breakpoints all the way through the page life cycle and found that nextButton and currentPageLabel are never initialised. The breakpoints were placed at OnLoad, CreateChildControls, goButton_Click, OnPreRender, Render and OnUnload.
Is it possible you've inadvertently got local variables named currentPageLabel and/or nextButton declared somewhere? The compiler will happily allow this...
This is especially common in a move from ASP.NET 1.1 to 2.0 or higher, since the way the designer defined these controls changed.
The problem was that all of the controls that weren't being initialised were inside a HeaderTemplate within a Repeater control. (To save space I didn't paste all of my code into the question, dang it.)
I moved them out and the problem is resolved. Obviously controls in the HeaderTemplate are instantiated by the Repeater and do not follow the normal page life cycle.

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