if i set EnableViewState="false" then also input data is maintain after postback at the time of using control like
textbox
radio button
checkbox
etc.
So I just wanted to know bit internal things that if EnableViewState="false" then how input data is maintain after postback when we are using control like textbox, radio button checkbox etc. please discuss the internal issue.
Thanks.
here is my aspx code
<%# Page Language="C#" AutoEventWireup="true" EnableViewState="false" CodeBehind="WebForm2.aspx.cs" Inherits="WebApplication1.WebForm2" %>
<asp:TextBox ID="TextBox1" runat="server"
style="position: relative; top: 0px; left: 0px;"></asp:TextBox>
<asp:TextBox ID="TextBox2" runat="server"
style="position: absolute; top: 66px; left: 11px; z-index: 1;"></asp:TextBox>
<asp:RadioButton ID="RadioButton1" runat="server" style="position: relative" />
<asp:CheckBox ID="CheckBox1" runat="server" style="position: relative" />
<asp:Button ID="Button1" runat="server" Text="Button" />
</div>
</form>
Input data is maintained because the browser sends the input data to the server on every postback. For example, the textbox on the page has its text sent to the server every time there is a postback. Therefore, the text property does not need to be stored in view state in order to be remembered across postbacks.
For much more information on view state, check out this article: Understanding ASP.NET View State.
Take a look at Server controls persist their state when EnableViewState is set to False
Example: Consider backcolor setting programmatically. On postback, if viewstate is switched off, the background color of the Textbox control is lost. However, the text value of the control is maintained.
Note: If the backcolor was set directly in markup rather than in code behind, it would have persisted.
<form id="form1" runat="server">
<asp:TextBox ID="Textbox1" runat="server" EnableViewState="false"></asp:TextBox>
<asp:Button ID="Button1" runat="server" Text="Button" EnableViewState="false" />
</form>
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
this.Textbox1.BackColor = Color.Yellow;
}
}
Also refer
Understanding ASP.NET View State
View State for TextBox and other controls that implement IPostBackDataHandler
How do I disable viewstate for a specific control?
Related
I've create my own UserControl called 'ReevooBadge' and have placed it in my listview by registering my UserControl. However, my UserControl isn't visible in the ListView. Any sugestions for this problem?
This is my User Control
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="ReevooBadge.ascx.cs" Inherits="KiaEurope2010.Website.controls.Addons.Widgets.ReevooBadge" %>
<a class="reevoomark <%= this.ClassName %>" href="//mark.reevoo.com/partner/<%= this.CountryCode %>/series:<%= this.SelectionIdentifier %>"><%= this.ReviewsTitle %></a>
I need to implement this in my ListView by the following code implementation
<asp:ListView ID="lvItemCarousel" ItemPlaceholderID="carrouselitems"OnItemDataBound="lvItemCarousel_ItemDataBound"
runat="server">
<layouttemplate>
<asp:PlaceHolder ID="carrouselitems" runat="server" />
</layouttemplate>
<itemtemplate>
<li>
<asp:HyperLink runat="server" ID="hlItem">
<asp:Image runat="server" ID="imItem" />
<div class="modelTitle">
<asp:PlaceHolder runat="server" ID="phReevoo" Visible="false">
<rhm:ReevooBadge runat="server" ID="ReevooBadge" />
</asp:PlaceHolder>
</div>
</asp:HyperLink>
</li>
</itemtemplate>
</asp:ListView>
Above I register my custom User Control
<%# Register Src="~/controls/Addons/Widgets/ReevooBadge.ascx" TagPrefix="rhm" TagName="ReevooBadge" %>
And in the Item Data Binding
protected void lvItemCarousel_ItemDataBound(object sender, ListViewItemEventArgs e)
{
//...
phReevoo.Visible = true;
ReevooBadge.ModelItem = this.Item;
ReevooBadge.CountryCode = KiaEurope.SitecoreLayer.Reevoo.Settings.GetReevooKey(LanguageCountryCultureHelper.CurrentCountryCode, Sitecore.Context.Language);
}
However, the user control isn't visible in the ListView.
I'm not sure how you're getting your code to compile because I couldn't reference phReevoo (the placeholder control) directly in the ItemDataBound event.
I needed to use the following:
e.Item.FindControl("phReevoo").Visible = true;
The same would apply if you tried to reference ReevooBadge.
To make the testing easier I created a web user control and used this as a substitute for your custom user control. After binding to a simple List<string>, the control showed without issue.
I would suggest checking if your user control is actually rendering outside of the ListView.
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
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.
I have a repeater with a RadioButtonList inside the ItemTemplate, but when the RadioButtonList.OnSelectedIndexChanged event fires it generates a full postback. What have I done wrong in my code below? How can I get the OnSelectedIndexChanged to generate an Async Postback?
<asp:UpdatePanel runat="server" ID="UpdatePanel2">
<ContentTemplate>
<asp:Repeater ID="Repeater1" runat="server" DataSourceID="sqlOptions">
<ItemTemplate>
<asp:UpdatePanel runat="server" ID="pnlA">
<ContentTemplate>
<strong>
<%# Eval("Name") %></strong><br />
<asp:RadioButtonList ID="RadioButtonList1"
DataSourceID="sqlOptionValues" runat="server"
DataTextField="id" DataValueField="Id" AutoPostBack="true"
OnSelectedIndexChanged="LoadPrice"
ValidationGroup="options" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator1"
ForeColor="Red" runat="server"
ControlToValidate="RadioButtonList1"
ErrorMessage="Required Field"
ValidationGroup="options" />
<asp:SqlDataSource ID="sqlOptionValues" runat="server"
ConnectionString="<%$ ConnectionStrings:
ConnectionString6 %>"
SelectCommand='<%# "SELECT DISTINCT OptionValue.Name,
OptionValue.Id FROM CombinationDetail
INNER JOIN OptionValue
ON CombinationDetail.OptionValueId = OptionValue.Id
WHERE (OptionValue.OptionId =" +
Eval("Id") + ")" %>'>
</asp:SqlDataSource>
<br />
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
</asp:UpdatePanel>
Many thanks for any help :)
This is a real-world use case. I have a page with Repeaters, Ajax Accordions inside of other Accordions, Update Panels inside other Update panels, you name it. The page works great, except when I want to update one of the Accordion panels with my RadioButtonList (RBL). Even with the RBL inside an update panel, it causes a postback of the entire page. I tried everything. I finally realized it wasn't me when I noticed my buttons would work just fine. I figure it must be a bug in either the framework or the Ajax Control Toolkit. I did find people reference this link all over the web (http://blog.smarx.com/posts/the-case-of-the-radiobuttonlist-half-trigger.aspx), but this link from 2007 is dead now and probably no longer applicable, so that's no help.
What I ended up doing was going with what works - that submit button. All I did was add an onclick attribute to the RBL to call a hidden button. Now you don't want to set the button to Visible=false because then the button won't appear in the generated markup. Instead, set the button's style to display:none; so that no one will see this hack, because yes, that's what this workaround is - it's a hack, but simple and just as effective as what you'd expect. Don't forget to remove the Autopostback="True" from your RBL.
CAVEAT: Because I'm using a hacked button for the onclick event, it's possible for the user to click in the area of the RBL, but not actually select an item. When this happens, our onclick triggers an AsyncPostBack and the codebehind logic will be processed, so please keep that in mind. To give you an idea of what I mean: all the Page_Load() events will be called, but rbl_Questions_SelectedIndexChanged() won't be if they happen to click in the area of the RBL without actually selecting an item. For my purposes this causes no issues in my logic and has no effect on the user.
Here's the Code:
Somewhere In the .Aspx Page:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:RadioButtonList ID="rbl_Questions" runat="server"
OnSelectedIndexChanged="rbl_Questions_SelectedIndexChanged">
</asp:RadioButtonList>
<asp:Button ID="btn_rbl_Questions" runat="server" style="display:none;"/>
<asp:Label ID="lbl_Result" runat="server" Text="" Visible="false">
</asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
In the Page_Load() event:
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack == false)
{
//Instead of using the AutoPostback of the RBL, use this instead.
rbl_Questions.Attributes.Add("onclick",
"document.getElementById('"
+ btn_rbl_Questions.ClientID
+ "').click();");
//Bind your RBL to a DataSource, add items programmatically,
// or add them in the aspx markup.
}
}
In the rbl_Questions_SelectedIndexChanged() event:
protected void rbl_Questions_SelectedIndexChanged(object sender, EventArgs e)
{
//Your code here.
//My code unhid the lbl_Result control and set its text value.
}
Update 05/24/2011
The above "hack" is no longer necessary (I am leaving it above since this was marked as the answer by the author). I have found the best way to do this, thanks to this SO Answer:
Updatepanel gives full postback instead of asyncpostback
The code is much simpler now, just remove what I put in the Page_Load() method and remove the Button I used in the Aspx page and add ClientIDMode="AutoID" and AutoPostBack="True" to the control you want the UpdatePanel to capture.
Somewhere In the .Aspx Page:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:RadioButtonList ID="rbl_Questions" runat="server"
ClientIDMode="AutoID" AutoPostBack="true"
OnSelectedIndexChanged="rbl_Questions_SelectedIndexChanged">
</asp:RadioButtonList>
<asp:Label ID="lbl_Result" runat="server" Text="" Visible="false">
</asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
MS changed how ClientID's are generated in .net 4.0 from "AutoID" to "Predictable" and I guess the ScriptManager or UpdatePanel's weren't updated correctly to use it. I can't find documentation on why that is anywhere or if it was left that way by design.
I seriously don't miss winforms.
Try this:
<asp:UpdatePanel runat="server" UpdateMode="Conditional" ID="pnlA">
You'll also need to setup
<Triggers>
//radio buttons
</Triggers>
Not sure how you'll do that since it's a dynamically built list.
I have a page with a listview that shows something like posts. On each post there should be a "rate box" which works similar to the "Like" button in facebook. The rate box is a User Control, that has an update panel inside it.
If I put the control with some random values in the page it works great - but when I put it inside the ListView, where it should be located, it won't work. The method is being called, but nothing happens.
I simplified the code a bit to make it easier to understand:
The "rate box" control:
protected void OnRateClick(object sender, ImageClickEventArgs e)
{
Rate++;
RateAmountLiteral.Text = Rate.ToString();
RateButton.Visible = false;
FeedbackLiteral.Visible = true;
rateButtonPanel.Update();
}
ascx:
<div class="rate_div">
<asp:UpdatePanel ID="rateButtonPanel" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<fieldset>
Rate:
<asp:Literal ID="RateAmountLiteral" runat="server"></asp:Literal>
<asp:ImageButton ID="RateButton" runat="server" ImageUrl="icn_rate.png"
OnClick="OnRateClick" />
<asp:Literal ID="FeedbackLiteral" runat="server" Visible="false">Thanks for rating!</asp:Literal>
</fieldset>
</ContentTemplate>
</asp:UpdatePanel>
</div>
aspx (using the control):
<asp:ListView ID="PostsView" runat="server" ItemPlaceholderID="itemPlaceHolder2"
<LayoutTemplate>
<div class="posts_div">
<asp:PlaceHolder ID="itemPlaceHolder2" runat="server" />
</div>
</LayoutTemplate>
<ItemTemplate>
<div class="post_div">
<div class="post_body">
<%# CurrentPost.Body %>
</div>
<UC:RatingBox id="RatingBox" runat="server"
PostID="<%# CurrentPost.ID %>"
Rate="<%# CurrentPost.Rate %>"/>
By: <a href="<%# CurrentPost.Author.LinkToProfile %>">
<%# CurrentPost.Author.DisplayName %>
</a> |
<%# CurrentPost.LiteralTime %>
</div>
</ItemTemplate>
</asp:ListView>
While debugging I noticed the controls in the method "OnRateClick" are empty and don't contain the right values. Please advice.
Also if you have any comments about the way I did things, don't hold yourself.
Thanks
There are a lot things that you may not have set up, I cannot tell from just the code snippet you have given. But make sure you do the following: -
1) Place a ScriptManager "" on the page.
If you are using master page in your application and your web page uses the master page, place script manager in master page. Or alternatively,you can also place script manager on specific web pages anyway.
2) Add a Triggers for the button RateButton in your Update panel.