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FindControl() always returns null from DataList Textbox

I have 8 items in a SQL table with a Description, ItemNumber, and ImagePath.
protected void Page_Load(object sender, EventArgs e)
{
//fill the datalist for the Signs Table
string tCallFrom = "Program." + System.Reflection.MethodBase.GetCurrentMethod().Name;
string tQry = #"SELECT * FROM [js_Signs]";
DataTable tblSigns = objCommMethods.fReturnTableFromQry(clsDBSelect.enumDBSelect.ProjectMaster, tQry, tCallFrom);
SignsList.DataSource = tblSigns;
SignsList.DataBind();
}
I am using a DataList to show all of the items along with a textbox that will allow a user to input the number of items they want:
<asp:DataList ID="SignsList" runat="server" RepeatColumns="4" CellPadding="2" Width="90%" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<table>
<tr>
<th>
<%#DataBinder.Eval(Container.DataItem, "Description") %>
</th>
</tr>
<tr>
<th>
<%#DataBinder.Eval(Container.DataItem, "ItemNumber") %>
</th>
</tr>
<tr>
<td>
<asp:Image ID="SignImage" runat="server" ImageUrl='<%#DataBinder.Eval(Container.DataItem, "ImagePath") %>' />
</td>
</tr>
<tr style="text-align: center;">
<td>
<asp:TextBox ID="txtSignQuantity" runat="server" CssClass="txtBox" BackColor="White" Enabled="true"
type="number" min="0" ToolTip="Please choose quantity of signs needed."/>
</td>
</tr>
<tr>
<td>
<p> </p>
</td>
</tr>
</table>
</ItemTemplate>
</asp:DataList>
<div class="btnGroup">
<div class="btnDiv">
<asp:Button ID="btnSave" runat="server" Text="Save" CssClass="btnSave" Width="90px" Visible="true" OnClick="btnSave_Click"/>
</div>
<div class="btnDiv">
<asp:Button ID="btnCancel" runat="server" Text="Clear" CssClass="btnCancel" Width="90px" Visible="true" OnClick="btnCancel_Click"/>
</div>
</div>
After the saved button is clicked in C# I want to find out the value that a user entered but it is always returning null:
protected void btnSave_Click(object sender, EventArgs e)
{
TextBox txtSignQuantity;
string tempSignQuantity;
try
{
foreach (DataListItem item in SignsList.Items)
{
txtSignQuantity = item.FindControl("txtSignQuantity") as TextBox;
tempSignQuantity = txtSignQuantity.Text;
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
I also checked and the Count of SignsList.Items was 8, so I know that it is retrieving the correct information. Sorry, I've never used a Data List before so I'm not really sure how to go about this...

The short answer is that data binding on postback is causing the problem. Check the Page.IsPostBack property before doing data binding:
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
//fill the datalist for the Signs Table
string tCallFrom = "Program." + System.Reflection.MethodBase.GetCurrentMethod().Name;
string tQry = #"SELECT * FROM [js_Signs]";
DataTable tblSigns = objCommMethods.fReturnTableFromQry(clsDBSelect.enumDBSelect.ProjectMaster, tQry, tCallFrom);
SignsList.DataSource = tblSigns;
SignsList.DataBind();
}
}
ASP.NET WebForms attempts to abstract away the fact that the control instances that were used to render the page are not the same instances it has when handling postback events. Data binding compounds the abstraction because it has to create controls in response to the DataBind call, and then on postback, recreate them based on the ViewState it saved.
Initializing controls from ViewState happens on the Init event, so when the Load event is fired later in the page lifecycle and you call DataBind on the control, everything it restored gets wiped out and recreated.
As for why you were getting null, it may have been that the controls were wiped out but not recreated; it may have had to do with other event handlers that didn't get rewired after the second data binding.

umbraco user control form create it's own action

I need help with Umbraco user control.
I create a user control to get input from user.
ascx file
<form id="formRegister" runat="server">
<table>
<tr>
<td>
<asp:TextBox ID="txtUserName" type="text" placeHolder="User Name" runat="server" ClientIDMode="Static"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Button ID="btnSubmit" runat="server" ClientIDMode="Static" Text="Submit" OnClick="btnSubmit_Click" />
</td>
</tr>
</table>
the ascx.cs file
protected void Page_Load(object sender, EventArgs e)
{
var b = 0;
}
protected void btnSubmit_Click(object sender, EventArgs e)
{
var a = 0;
}
but somehow when it's loaded i get this in firebug
<form id="formRegister" action="/register/" method="post">
So the form create it's own action and do that action when I click the submit button instead of the btnSubmit_click event.
What should I do?

User controls won't fire their on click events when loaded as a macro in an Umbraco MVC site. Create a partial view and surface controller instead.

How can I prevent C# from redrawing a <div> I used jQuery to show

Scenario: I have a modal-style div that will be shown when the user clicks a button. At the time the div is shown, I need to get some data from the back-end to fill in some fields. Additionally, I'd like to use the jQuery method I use for all my modal windows (fades in the modal div, displays a background div as well as enabling the use of ESC key or "click offs" to close the modal).
It looks something like this:
<asp:ScriptManager ID="sc" runat="server" />
<asp:UpdatePanel ID="updForm" runat="server">
<ContentTemplate>
<h4>Testing jQuery calls combined with code behind actions</h4>
<div class="pad-content">
<asp:LinkButton ID="lnkShowIt" runat="server" OnClick="lnkShowIt_Click" Text="Load Form" OnClientClick="showForm()" />
<asp:Panel ID="pnlPopup" ClientIDMode="Static" runat="server" CssClass="box-modal" style="width:500px;display:none;z-index:1001">
<div class="header">Edit Estimate X</div>
<div class="content">
<div class="window">
<h5>Test Form</h5>
<asp:TextBox ID="tbxTime" runat="server" />
<br />
<asp:TextBox ID="tbxText" runat="server" Width="150px" />
<br />
<asp:LinkButton ID="lnkValidate" runat="server" CssClass="link-button-blue" Text="Validate" OnClick="lnkValidate_Click" />
</div>
</div>
</asp:Panel>
</div>
</ContentTemplate>
</asp:UpdatePanel>
<div id="backgroundPopup"></div>
So ... lnkShowIt calls both the jQuery (which will show pnlPopup) as well as the C# (which will populate tbxTime).
jQuery method actually just calls another method from a common js library I have that does the modal window stuff - I don't think that actual code is the problem but here is the simple function used for this page:
<script type="text/javascript" language="javascript">
function showForm() {
loadPopup('#pnlPopup');
}
</script>
Code behind methods look like this:
protected void lnkShowIt_Click(object sender, EventArgs e)
{
tbxTime.Text = System.DateTime.Now.Second.ToString();
}
protected void lnkValidate_Click(object sender, EventArgs e)
{
if (tbxTime.Text == tbxText.Text)
{
Response.Redirect("DynamicBoxesWithJQuery.aspx?mode=success");
}
else
{
tbxText.Style["border"] = "1px solid red";
}
}
I'm able to generate some level of success by doing the following but it seems like just a major hack and I have to assume there's a better approach:
protected void lnkShowIt_Click(object sender, EventArgs e)
{
tbxTime.Text = System.DateTime.Now.Second.ToString();
ScriptManager.RegisterStartupScript(this, this.GetType(), "OpenEditor", "<script type='text/javascript'>loadPopup('#pnlPopup');</script>", false);
}
protected void lnkValidate_Click(object sender, EventArgs e)
{
if (tbxTime.Text == tbxText.Text)
{
Response.Redirect("DynamicBoxesWithJQuery.aspx?mode=success");
}
else
{
tbxText.Style["border"] = "1px solid red";
ScriptManager.RegisterStartupScript(this, this.GetType(), "OpenEditor", "<script type='text/javascript'>loadPopup('#pnlPopup');</script>", false);
}
}
It seems like it should be easier than this, but the way the UpdatePanel keeps redrawing (and thus resetting the display:none on pnlPopup) is really causing me fits.
Thanks in advance

Solution I just found: putting the LinkButton in its own UpdatePanel and then the form in its own UpdatePanel and making sure the div that is the actual popup box is not in an UpdatePanel at all.
<h4>Testing jQuery calls combined with code behind actions</h4>
<div class="pad-content">
<asp:UpdatePanel ID="updLink" runat="server">
<ContentTemplate>
<asp:LinkButton ID="lnkShowIt" runat="server" OnClick="lnkShowIt_Click" Text="Load Form" OnClientClick="showForm()" />
</ContentTemplate>
</asp:UpdatePanel>
<asp:Panel ID="pnlPopup" ClientIDMode="Static" runat="server" CssClass="box-modal" style="width:500px;display:none;z-index:1001">
<div class="header">Edit Estimate X</div>
<div class="content">
<asp:UpdatePanel ID="updForm" runat="server">
<ContentTemplate>
<div class="window"style="min-width:500px;">
<h5>Here is a Test Form</h5>
<label>Time:</label>
<asp:TextBox ID="tbxTime" runat="server" />
<br />
<asp:Label ID="lblText" AssociatedControlID="tbxText" runat="server" ViewStateMode="Disabled">Text:</asp:Label>
<asp:TextBox ID="tbxText" runat="server" Width="150px" />
<br />
<asp:LinkButton ID="lnkValidate" runat="server" CssClass="link-button-blue" Text="Validate" OnClick="lnkValidate_Click" />
</div>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</asp:Panel>
</div>
Seems to do the trick without any Script Registers from the codebehind

How to retrieve details from a repeater control to display in modal popup

I have a repeater control which displays an image and some basic information like DateTime and Prouct Id. On clicking an Image I need to run another query and show details in a seperate popup.I know how to do the popup.
I want to know how I can fetch the DateTime and ProductId from the repeater and use them in the button click event of the image?
I have my code for the repeater below :
<asp:Repeater ID="rptMonitorSummary" runat="server" OnItemDataBound="rptMonitorSummary_OnItemDataBound">
<ItemTemplate>
<asp:Panel ID="Pnl" runat="server">
<li class="ui-widget-content ui-corner-tr">
<h5 class="ui-widget-header">
<%# Eval("Name").ToString().Length > 9 ? (Eval("Name") as string).Substring(0, 9) : Eval("Name")%>
</h5>
<div id="divHover">
<asp:ImageButton Width="80px" ID="btnPerformanceImage" onclick="btnPerformanceImage_Click" runat="server" Height="45px">
</asp:ImageButton>
</div>
<div class="tooltip" style="display: none">
<div style="text-align: center; font-weight: bold;">
<%# Eval("DateTime") %><br />
</div>
<div style="text-align: center; font-weight: normal">
ErrorRatingCalls =
<%# Eval("ProductId")%><br />
</div>
<div style="text-align: center; font-weight: normal">
TotalRatingCalls =
<%# Eval("TotalCalls")%>
<br />
</div>
<div style="text-align: center; font-weight: normal">
SuccessRate =
<%# Eval("PassPercentage") + "%" %>
</div>
</div>
</li>
</asp:Panel>
</ItemTemplate>
</asp:Repeater>
I also have the button click event below :
protected void btnPerformanceImage_Click(object sender, EventArgs e)
{
ScriptManager.RegisterStartupScript
(this, this.GetType(), "callScriptFunction", "ViewModelPopup1();", true);
}
All I want to know is how I can fetch the values that are already bound to the repeater control, When I click on an image which inside the repeater control

Instead of handling click on the button itself, you should rather make use of ItemCommand event of the Repeater control. As a CommandArgument you can pass ProductId, and then inside the handler use it to retrieve rest of the info from the DB. Or you can even include all needed values into CommandArgument as a single string and do some parsing afterwards:
<asp:Repeater ... OnItemCommand="rptMonitorSummary_ItemCommand" ... >
...
<asp:ImageButton ... CommandName="ShowPopup" CommandArgument='<%# Eval("ProductId") + "," + Eval("DateTime") %>'>
</asp:ImageButton>
...
</asp:Repeater>
The handler might look like this:
protected void rptMonitorSummary_ItemCommand(object sender, RepeaterCommandEventArgs e)
{
string[] tokens = e.CommandArgument.ToString().Split(',');
int productId = int.Parse(tokens[0]);
DateTime dateTime = Date.Time.Parse(tokens[1]);
// the rest of the handling here
}

Use the OnItemCommand event to fetch values out of the repeater control.
<asp:Repeater ID="rptMonitorSummary" runat="server" OnItemDataBound="rptMonitorSummary_OnItemDataBound" OnItemCommand="rptMonitorSummary_ItemCommand">
.
.
.
<asp:ImageButton Width="80px" ID="btnPerformanceImage" CommandName="Popup" runat="server" Height="45px"></asp:ImageButton>
.
.
.
protected void rptMonitorSummary_ItemCommand(object source, RepeaterCommandEventArgs e)
{
if (e.CommandName == "Popup")
{
DataRowView row = ((DataRowView)e.Item.DataItem).Row;
string data1 = Convert.ToString(row["Data1"]);
string data2 = Convert.ToString(row["Data2"]);
ScriptManager.RegisterStartupScript
(this, this.GetType(), string.Format("callScriptFunction", "ViewModelPopup1('{0}','{1}');", data1, data2), true);
}
}

Rather than the OnClick inside your Button, use the OnItemCommand="rptMonitorSummary_ItemCommand" in your Repeater
Then on the code behind
protected void rptMonitorSummary_ItemCommand(object sender, RepeaterCommandEventArgs e)
{
// e.CommandName and e.CommandArgument will let you know what was clicked
}
Your button can look something like this
<asp:Button runat="server" ID="btnPerformanceImage" Text="Whatever" CommandName="OpenImage" CommandArgument='<%# DataBinder.Eval(Container.DataItem, "ProductId") %>' />
So then you know what the user clicked on and can change the popup to suit it

you can set a class attribute name for both div tags wich contains the date value and ProductId value and next get them with jquery .find('classname') to retreive their values.

ListView Visible property

I have a search results page where the list views visible property is always false on the first page load even though I set the value to true as seen below. It seems line is being ignored? Is there a reason why this property cannot be set on the first load?
EDIT: Page load Event
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
if (Request.QueryString["query"] != null)
{
_searchTerm = Request.QueryString["query"].ToString();
GetSearchResults();
txtSearchBox.Text = _searchTerm;
}
}
}
ListView Markup
<asp:PlaceHolder runat="server" ID="SearchResults" Visible="false">
...
<asp:ListView id="lvSearch" runat="server">
<LayoutTemplate>
<ul id="SearchResultsList">
<asp:PlaceHolder runat="server" ID="itemPlaceholder"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li class="searchResult">
<h2><%#DataBinder.Eval(Container.DataItem, "Title")%></h2>
<p><%#DataBinder.Eval(Container.DataItem, "HighlightedPreview")%></p>
<%#DataBinder.Eval(Container.DataItem, "URL")%>
</li>
</ItemTemplate>
</asp:ListView>
<div runat="server" id="NoResults" visible="false">
<p>The current search has returned no results. Please enter another search term in the box above.</p>
</div>
</asp:PlaceHolder>

Check that it is not in the DIV-NoResults or some other container that is going invisible.