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Why Eval does not display label and textbox?

I retrieve some html codes from database and I want to display this values in a webform.
You can see my code below. It does not display labels and textboxes. However when I View the .aspx page source in the browser I can see retrieved labels and textboxes with Eval. Why I can not see labels and textboxes in the page?
database values:
code behind:
using (BurganEntities burganEntities = new BurganEntities())
{
List<DynamicField> dynamicFields=(from dynamicField in burganEntities.DynamicField select dynamicField).ToList();
cdcatalog.DataSource = dynamicFields;
cdcatalog.DataBind();
}
aspx:

The fast answer is because asp,net controls are compiled server side but you using them as text on the final render html page - so you have skip this compile, and the asp.net page did not know nothing about them.
The solution is to avoid asp.net controls and use regular html controls. You can still get their return on code behind, you may miss some easy to use functionality, but you can make your work with alternative way.
Other possible solution is to read the database and dynamically create the controls. For example you can add a flag on your database line that says, now create a text box, and on code behind you just create that text box dynamically.

Your code is simply outputting the <asp:TextBox /> to the browser; it isn't parsing it with the WebForms processor to convert it to an <input /> element.
In your database, you should probably be storing:
<input id="txtsdsd" name="txtsdsd" class="textbox" onkeypress="return NumberOnly()" />
and then using Request.Form() to retrieve the value.

I'm not sure if you've started to write your dynamic controls but as an addition to second reply, I would like to mention more sources about dynamic controls.
Although there is no concept of controls in ASP.NET MVC any longer, you can follow ASP.NET webform data access page.
As you want to compile your code at server side; on any postback you will loose dynamic content. So read this and all done.
Or as you mentioned you didn't get values of textboxes, please see the following method,
var textBox = FindControl("<id_of_textbox>") as TextBox;
if(textBox != null)
{
var textBoxValue = ((TextBox)textBox).Text;
}
</id_of_textbox>
see FindControl method at this page

In a C# MVC app is it possible to submit variables from a web page in controls that did not change?

I have a C# MVC application and a <form> in my page.cshtml file. In that form I have <input type="text" ... /> elements. If I submit this form I only get the values in Response.Params or Response.Form from the inputs where I changed the value manually (i.e. Entered the text box then typed something).
If I change the value with jQuery, $('#myInput').val('some value'); this does not count as a change in the input's value and I do not get myInput's value when I submit the form.
Is there any way to make sure all inputs are submitted? If not then is there a good workaround for this, maybe in some event that occurs before my model gets bound? I need to know all the input values from the form when submitted whether they changed or not.
Some additional info:
The form and other values are getting submitted correctly and I am receiving my model when the POST action is called in my controller.
The real issue is when my model is being bound. It is being created and bound with all values except the one not being submitted because it is not in the Request.Params collection.

I have only ever seen this behaviour when a field is disabled. Due to this, I commonly have a javascript function that handles the form submission and re-enables them on submit, this way the correct values get sent to the server.
Something like this does the trick for me (NOTE: I am using JQuery):
$(document).ready() {
$("#ButtonSubmit").click(SubmitForm);
}
function SubmitForm(e) {
e.preventDefault();
//ensure fields are enabled, this example does text and checkbox types
$("[type='text']").attr("disabled", false);
$("[type='checkbox']").attr("disabled", false);
//submit the form
document.forms[0].submit();
}
I am unaware of any easier way to do this, it would be nice if you could 'flag' something that instructs all fields to be submitted. But I don't know if this exists, maybe somebody else can offer a better solution.
EDIT: It appears that disabled fields not submitting is just the nature of HTML, and is not something that is tied to MVC.
It seems that if you make the fields readonly instead of disabled then the values will still submit. However, with this approach you lose the 'disabled' styling. The exception to this rule is select control, it seems this will not submit under readonly either. More information on this can be in this question

Try using the razor helper to build the form tag.
#using(Html.BeginForm()) {
..
// make sure this is a submit button
<input type="submit" value="Save" />
}
In your controller action post method make sure you decorate it [HttpPost].
e.g.,
[HttpPost]
public ActionResult Edit(YourModel model) {
}

how to get <input of type=hidden> with FindControl

I am trying to get the value of a hidden input in code behind with the following code. I am trying to cast it but it cannot find it , any help ?
((HtmlControl)FindControl("contentId"))
I declare it in aspx with the following code:
<input id="contentId" type="hidden" />
I dont want to runat server because i have my own reasons

To access a HTML control at server side (in your C# code), you need to first add the runat="server" attribute. So, your markup should look like
<input type="hidden" id="contentId" runat="server"/>
Now, in the code behind you can use the control by its id contentId itself if the code behind got generated properly.
Please let us know why you are forced to use the FindControl in the first place as it can be accessed by using the id directly.
Update
As per the comment below, the user for some reason is not interested in making this input a server side control. Then the only possibility by which you can read the values at server side is as below. But this is not advised as any changes to the name goes unnoticed and breaks at runtime.
<input type="hidden" id="contentId" name="contentName" runat="server"/>
In Code
this.Request.Forms["contentName"] would return the hidden value.

Try to search it on the page this way
HiddenField hf = (HiddenField)page.FindControl("contentId");

To get the value:
HiddenField h = (HiddenField)Gridview.FindControl("HiddenFieldName");
Then with that you can put it into a string, if you wish to.

Use this code:
string s=((HiddenField)Panel1.FindControl("contentId")).Value;
Here panel is the container control. This may be a grid or anything else or even a master page. But if you are using FindControl, i think the control may be inside some container.

HtmlInputHidden hf = Page.FindControl("contentId") as HtmlInputHidden;
string hfValue = hf.Value;

How to submit a form without postback in asp.net?

I have a form in asp.net webpage which contains 2 drop down lists and a hyperlink + a button.
I want that if user changes an option is dropdowns to change navigate url.
I have done like so:
<asp:DropDownList ID="ddlPackages" AutoPostBack ="true" runat="server"
onselectedindexchanged="ddlPackages_SelectedIndexChanged"></asp:DropDownList>
and then I have the method defined.
The point is that I don't want to make a submit when I change the drop down. Can I do it using only aspx or I have to use javascript?

If I understand you correctly you want to change the href of the hyperlink based on the selected value of the dropdown. You can do this with javascript. Make sure you have AutoPostBack="false" and remove the OnSelectedIndexChanged attribute as well.
To do it using jQuery, use something like this:
<script type="text/javascript>
$(function(){
var $dropdown = $('#<%= ddlPackages.ClientId %>');
$dropdown.change(function(){
//Put logic to decide the link here based on the select value
var newPage = 'page' + $dropdown.val() + '.aspx';
$('#linkId').attr('href', newPage);
});
});
</script>
Edit:
In case you absolutely must have the logic for getting the new url based on the drop down value on the server side, you can turn the method into a Page Method and call it using ajax from the jQuery script above. But you can probably get away with creating the javascript dynamically in the aspx page instead.

I see two options:
1) Wrap the controls in an Update Panel (.NET 3+). Put AutoPostBack=true on the dropdownlist, and define a SelectedIndexChange event for it that changes the hyperlink control's Navigate URL property. When the user changes the dropdown, you're method will fire without the APPEARANCE of a form submission. Downside: there's a slight delay between the dropdown changing and the link changing. If your server is really, really slow, this delay could potentially cause problems (but this is probably unlikely).
2) Use custom JavaScript and do away with your .NET controls completely. This is what I would probably do, assuming you don't need to do anything else with these controls programatically. Your JavaScript function would monitor the dropdown for a SelectedINdexChange and adjust the href attribute of the anchor tag accordingly. Look into jQuery to speed up development if you aren't too familiar with plain JavaScript.

If the control is an ASP:DropDownList, you can use the AutoPostBack="True|False" property to prevent a postback

If you don't want to use the AutoPostBack you have to post the form using jQuery or Javascript
You can add an event on your drop down list onchange and add the code you need to post the form usin jQuery:
$('#formId').submit();
http://api.jquery.com/submit/
If you to want navigate to another Url add the below code at your DropDownList control (make sure AutoPostBack=false)
onchange="window.location.href='yourUrl'"
it would be better put that Javascript on a separate file anyway

Set attribute with JS and grab it by controlID in code-behind

After postback, attributes are cleared.
So how can I send an attribute applied to controlID via JS to the next request page?
Thanks in advance!

Javascript and ASP.Net controls can have a rather strained relationship. The main thing to remember is that ASP.Net needs to be able to get a value/see a change. Custom attributes may not be kept during a post back.
Have you tried storing the info using a hidden control?
<asp:HiddenField ID="id" Value="value" />
MSDN ref