Develop Reference

Unusable elements inside the (list view ) asp.net

Why can't I use the (input) I put in my (list view) in the C # code field?
<asp:ListView ID="ListV" runat="server">
<ItemTemplate runat="server">
<asp:Label ID="Label2" runat="server" Text="Label"></asp:Label>
<tr class="text-center">
<td class="product-remove"></td>
<td class="image-prod">
<div class="">
<asp:Image ID="Image1" CssClass=" img" ImageUrl='<%# "../img/" + Eval("picture")
%> ' runat="server" />
</div>
</td>
<td class="product-name"><%# Eval("namebook") %> </td>
<td class="price"><%# Eval("Price") %> </td>
<td class="quantity"><%# Eval("titel") %></td>
<td class="col-2">
<asp:Button ID="delete" CssClass="btn btn-outline-danger" CommandArgument='<%#
Eval("id")%>' OnClick="delete_Click" runat="server" Text="حذف کالا" />
</td>
<td>
<input id="quantity2" runat="server" type="number" value="1" min="1" max="20" />
</td>
</tr>
</ItemTemplate>
</asp:ListView>

You want a server control there. Additionally, this control only exists as part of an item template, meaning there isn't just one control named quantity2... there could be many, depending on the data source. Therefore referencing it just by name is not good enough. And speaking of data sources, depending on how you handle this the databinding may not have taken place yet at the time the Page_Load code runs, meaning the input control doesn't exist at all.
So the real question is: what do you want to do with this input?

CodeBehind="~/ (Page Name) .aspx.cs"

recursively step through asp table (that has been populated with a query)

so basically I have a query that populates a table in an asp page like so:
<div class="span10">
<table class="table table-bordered table-striped with-check" runat="server" id="noncompulsarymodules">
<tbody>
<tr>
<td><asp:Label ID="Label3" runat="server" Text= '<%# Eval("ModuleId") %>' style="display:none;" /> </td>
<td><asp:Label ID="Label1" runat="server" Text= '<%# Eval("noncompcode") %>' /> </td>
<td><asp:Label ID="Label2" runat="server" Text= '<%# Eval("noncomptitle") %>' /> </td>
<td><asp:Label ID="Label4" runat="server" Text= '<%# Eval("moduleunits") %>' /> </td>
<td class="center" style="overflow:hidden;"> <asp:Label ID="ModuleDescription" runat="server" Text='<%# Eval("noncompdesc") %>' /></td>
<td><input type="checkbox" /></td>
</tr>
</tbody>
</table>
</div>
basically what I want to do is cycle through the table and take the rows that have been checked and put them into a query.
Any tips would be greatly appreciated!

Have a look at using an ASP.Net Gridview control with a checkbox / templatefield column.
You will then be able to iterate through the GridViewRows and get the checked columns.

cascading drop down list does not load in page load event?

i have an user control in that i used cascading drop down for states,districts and areas...how to load cascading drop down in user control page load....cascading Drop down code is
<table>
<tr>
<td class="caption">
State:
<asp:DropDownList ID="ddlCState" runat="server" CssClass="userentry">
</asp:DropDownList>
<cc1:CascadingDropDown ID="cdlCStates" TargetControlID="ddlCState" PromptText="Select State"
ServicePath="~/CasCadingDropDown.asmx" ServiceMethod="GetStates" runat="server"
Category="StateId" LoadingText="Loading..." />
</td>
</tr>
<tr>
<td class="caption">
District:
<asp:DropDownList ID="ddlCDistrict" runat="server" CssClass="userentry">
</asp:DropDownList>
<cc1:CascadingDropDown ID="cdlCDistrict" TargetControlID="ddlCDistrict" PromptText="Select District"
ServicePath="~/CasCadingDropDown.asmx" ServiceMethod="GetDistricts" runat="server"
Category="DistrictId" ParentControlID="ddlCState" LoadingText="Loading..." />
</td>
</tr>
<tr>
<td class="caption">
Area:
<asp:DropDownList ID="ddlCArea" runat="server" CssClass="userentry">
</asp:DropDownList>
<cc1:CascadingDropDown ID="cdlCAreas" TargetControlID="ddlCArea" PromptText="Select Area"
ServicePath="~/CasCadingDropDown.asmx" ServiceMethod="GetAreas" runat="server"
Category="AreaId" ParentControlID="ddlCDistrict" LoadingText="Loading..." />
</td>
</tr></table>

New controls not recognized in code behind

I added a couple of fields manually in my ASPX page which is actually holding a FormView. By manually, I mean by directly typing code in the Markup editor.
Now when I'm trying to access those controls in the code behind, nothing comes up in intellisense.
I deleted the designer.cs file and right clicked the ASPX page and chose Convert to web application, still no go.
The designer file's got the FormView control defined alright, but nothing about its child controls.
Do I really need to use FindControl to get this working ? Tell me if you need some code posted because at the moment maybe I'm just a bit confused about ASP.NET is actually working (or not at this moment).
Here's the markup code:
<%# Page Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="True" CodeBehind="WebForm_PatientForm.aspx.cs" Inherits="WebAppWalkthrough.WebForm_PatientForm" Title="Employee form" %>
<%# MasterType VirtualPath="~/Site.Master" %>
<asp:Content ContentPlaceHolderID="HeadContent" runat="server">
</asp:Content>
<asp:Content ContentPlaceHolderID="MainContent" runat="server">
<asp:FormView ID="PatientForm" runat="server" DefaultMode="Edit">
<EditItemTemplate>
<table>
<tr>
<td class="FormViewHeader">
Patient Name:
</td>
<td>
<asp:TextBox ID="PatientName" ReadOnly="true" runat="server" Text='<%# Bind("FullName") %>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Patient ID:
</td>
<td>
<asp:TextBox ID="PatientID" ReadOnly="true" runat="server" Text='<%# Bind("patientid") %>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Eligibility
</td>
<td>
<asp:DropDownList runat="server" ID="Eligibility" SelectedValue='<%# Bind("service_executive_eligibility") %>' >
<asp:ListItem Value="" Text="N/A" />
<asp:ListItem Value="True" Text="Yes" />
<asp:ListItem Value="False" Text="No" />
</asp:DropDownList>
</td>
</tr>
</table>
<asp:LinkButton ID="LinkButton2" runat="server" OnCommand="UpdatePatientInfo" Text="UpdateInfo" CommandArgument='<%# Bind("patientid") %>'>Update</asp:LinkButton>
<asp:LinkButton ID="LinkButton3" runat="server" OnCommand="CancelEditPatient" CommandName="CancelUpdate" Text="CancelInfo">Cancel</asp:LinkButton>
</EditItemTemplate>
<InsertItemTemplate>
<table>
<tr>
<td class="FormViewHeader">
Employee First Name:
</td>
<td>
<asp:TextBox ID="FirstName" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Employee Last Name:
</td>
<td>
<asp:TextBox ID="LastName" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Email address:
</td>
<td>
<asp:TextBox ID="EmailAddress" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Work phone number:
</td>
<td>
<asp:TextBox ID="PhoneNumber" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="FormViewHeader">
Eligibility
</td>
<td>
<asp:DropDownList runat="server" ID="Eligibility">
<asp:ListItem Value="True" Text="Yes" />
<asp:ListItem Value="False" Text="No" />
</asp:DropDownList>
</td>
</tr>
</table>
<asp:LinkButton ID="LinkButton5" runat="server" OnCommand="AddEmployee" Text="Add Employee">Add</asp:LinkButton>
</InsertItemTemplate>
</asp:FormView>
</asp:Content>
Even if I add the controls manually in the designer file, I get a null reference error in the code behind at run time (even if intelisense picks up FirstName the object is null at runtime).
EDIT: I will try installing VS2010 SP1 and this hotfix I found and post the results.
EDIT 2: So I installed VS2010 SP1 which didn't solve the issue. I could not install the hotfix as my system is x64.
So I ditched VS2010 and tried with VS2013, which still doesn't pickup the markup controls.
Even Page.FindControl("ControlName") returns null. Something is very rotten with that webpage or VS2013...
Thanks.

I encountered a problem that seems similar with Telerik UI components for WebForms before. I wanted to access items that were defined inside of a template in a grid, but unfortunately the only way to do that was to dig into child elements of that grid. That inner elements were not present in the designer.cs file as well.
I am not sure about that, but it can be a common behavior of nested elements in WebForms.

Read textbox from ASP.net page that repeated n times

I have an asp.net web page that's has a number of controls that are repeated according to number of records retrieved from the database, and I wanna read the values of those text boxes after users enter values in them, so please if anyone can help me on this issue.
I have an example of my work
<% System.Data.SqlClient.SqlDataReader myDReader = myDatabaseConnector.getDataFromDBAsSQLDataReader("SELECT * from students);
while(myDReader.Read())
{ %>
<asp:TextBox ID="txtCourseInfo" Test="" EnableViewState="false" CssClass="dataEntrySearchDataText" ReadOnly="true" runat="server"></asp:TextBox>
<% } %>
This a sample of what I have mean from my question in which I want to retrieve the value of txtCourseInfo in my C# code behind

You could use a Repeater to do this:
<asp:repeater id="rptCourses" runat="server" DataSourceID="dsCourseInfo"
<ItemTemplate>
<asp:TextBox ID="txtCourseInfo" Text='<%#Eval("StudentName")#%>' EnableViewState="false" CssClass="dataEntrySearchDataText" ReadOnly="true" runat="server"></asp:TextBox>
</ItemTemplate>
</asp:Repeater>
<asp:sqldatasource id="dsCourseInfo"
ConnectionString="<%$ ConnectionStrings:YourConnectionString %>"
Select Command="Select * from Students">
</asp:sqldatasource>
That's all you need. from code behind you can iterate through the controls on the repeater and grab the information.
Notice the Eval expression on the text field. I used "StudentName" as an example, but you should use one of the column names returned by the select statement
Additional comments:
Don't do select * from ... It's a bad practice in many respects. Always specify the columns you need, even if you need all.
I realize that you disable viewstate on the textbox. I don't know the reason for doing this but be aware that the info won't be persisted on subsequent postbacks unless you enable it on the control.
UPDATE
Yes, you can have tables inside repeaters. Look at the example below:
<ItemTemplate>
<table runat="server" style="color: White; background-color: #3A4F63;" visible="false"
id="headerTable">
<tr>
<td colspan="3" align="center">
<asp:Label ID="headerTitle" runat="server"></asp:Label>
</td>
</tr>
<tr>
<td style="width: 200px; background-color: #3A4F63; color: White;">
Image
</td>
<td style="width: 200px;">
Studen Name
</td>
<td style="width: 200px;">
Birth Date
</td>
</tr>
</table>
<table>
<tr>
<td style="width: 200px;">
<asp:Image ID="img" runat="server" ImageUrl='<%#Eval("ImageUrl") %>'></asp:Image>
</td>
<td style="width: 200px;">
<asp:Label ID="lblName" runat="server" Text='<%#Eval("Name") %>'></asp:Label>
</td>
<td style="width: 200px;">
<asp:Label ID="lblBirthDate" runat="server" Text='<%#Eval("BirthDate") %>'></asp:Label>
</td>
</tr>
</table>
</ItemTemplate>