After trying to understand why client code is not rendered in a page (injected by user control) I found this link, it turns out you must have a form tag for it to work (Page.RegisterClientScriptBlock did declare this but ClientScriptManager.RegisterClientScriptBlock which I use does not say anything regarding this).
I am using Visual studio 2005.
Does anyone know if this has been solved?
Edit:
To clarify, I want my control to add javascript code to the head section of the page without having to use the
<form runat="server"
I have tried adding it using:
HtmlGenericControl x = new HtmlGenericControl("script");
x.InnerText = "alert('123');";
Page.Header.Controls.Add(x);
But this did not work for me.
As far as I know this functions the same in current versions, you can test it very simply though.
Update
per discussion in the comments, the only "workaround" that I could think of would be for your to manually insert the script into the "head" section of the page on your own, using a runat="server" declaration on the Head element.
Got it!
My mistake was not doing it in the OnPreRender method (I used the Render method).
Now all that is needed is - like Mitchel Sellers wrote, set the header to runat server and than add to it's controls:
HtmlGenericControl x = new HtmlGenericControl("script");
x.InnerText = GetScriptSection();
Page.Header.Controls.Add(x);
Thanks for pointing me to the right direction!
The MSDN Page for registerclientscriptblock here says:
The client-side script is emitted just
after the opening tag of the Page
object's <form runat= server> element.
The script block is emitted as the
object that renders the output is
defined, so you must include both tags
of the <script> element.
If you do not want to include a form, than you will basically need to build your own implementation of it.
Minor clarification for anyone seeing this:
The form tag must have the runat="server" attribute set, e.g.
<form id="theform" runat="server">
Just placing a regular HTML form tag in the page will not help.
Related
I have a hyperlink that in certain cases I want to change to show a jquery popup, but I'm having a strange problem when doing it on a master page. The following works in a regular page:
hyp1.NavigateUrl = "#notificationPopup";
Which renders as:
<a id="ctl00_hyp1" href="#notificationPopup">Example</a>
This is exactly what I want. The problem is with the exact same code on a hyperlink on the master page it renders as:
<a id="ctl00_hyp1" href="../MasterPages/#notificationPopup">Example</a>
It looks like it might be running the navigateUrl through ResolveClientUrl() or something when I'm setting it on the master page. I've tried swapping the <asp:hyperlink for a <a href runat=server, but the same thing happens.
Any ideas?
There is a note on MSDN Control.ResolveClientUrl method description.
The URL returned by this method is
relative to the folder containing the
source file in which the control is
instantiated. Controls that inherit
this property, such as UserControl and
MasterPage, will return a fully
qualified URL relative to the control.
So the behavior of master page in your exampe is fully predictable (although this is not a very comfortable to work with). So what are the alternatives?
The best one is to set the <a> as a client control (remove runat="server"); should work like a charm even in a master page:
Example
In the case if this control should be server side only: you could just build an URL from your code behind by using UriBuilder class:
UriBuilder newPath = new UriBuilder(Request.Url);
// this will add a #notificationPopup fragment to the current URL
newPath.Fragment = "notificationPopup";
hyp1.HRef = newPath.Uri.ToString();
Create a hidden field on your form and set the value to where you want to navigate / the url of the hyperlink instead of the hyperlinks navigate url. Then call the onclick method of the hyperlink in javascript and set the hyperlink there before the browser does the actual navigation.
<html><head><title></title></head>
<script type="text/javascript">
function navHyperlink(field)
{
field.href = document.getElementById('ctl00_hdnHypNav').value;
return true;
}
</script>
<input type="hidden" id="hdnHypNav" value="test2.html" runat="server"/>
<a href="" onclick="navHyperlink(this);" >click here</a>
</html>
Code behind would be:
hdnHypNav.value = "#notificationPopup";
You could also just try setting the url after the postback with below code, i.e. replace your code behind line with this one but I am not sure if it will work...
ScriptManager.RegisterStartupScript(this,this.GetType(),"SetHyp","$('ctl00_hyp1').href = '#notificationPopup';",True)
I found another way to solve the problem.
hyp1.Attributes.Add("href", "#notificationPopup");
Seeing as the whole reason I replaced my static hyperlink with a runat="server" one was to benefit from automatic resource-based localization, none of these answers served my needs.
My fix was to enclose the hyperlink in a literal:
<asp:Literal ID="lit1" runat="server" meta:resourcekey="lit1">
Example
</asp:Literal>
The downside is if you need to programmatically manipulate the link, it's a bit more annoying:
lit1.Text = String.Format("Example", HttpUtility.HtmlAttributeEncode(url));
I have my UserControls in a ~/Controls folder in my solution:
/Controls/TheControl.ascx
If specify the following:
<a id="theId" runat="server" href="./?pg=1">link text</a>
ASP.Net seems to want to rewrite the path to point to the absolute location. For example, If the control is on site.com/products/fish/cans.aspx the link href will be rewritten to read
<a id="munged_theId" href="../../Controls/?pg=1>link text</a>
Why does Asp.Net rewrite these control paths, and is there an elegant way to fix it?
I just want the anchor control to spit out exactly what I tell it to!!! Is that so hard?
EDIT:
I've basically done what Kelsey suggested. I knew I could do it this way, but I don't like adding markup in my code when I want something relatively simple. At least it solves the problem:
Aspx page:
<asp:PlaceHolder ID="ph" runat="server"></asp:PlaceHolder>
Code-behind:
var anchor = new HtmlGenericControl("a") { InnerText = "Previous" + " " + PageSize) };
anchor.Attributes["href"] = "?pg=" + (CurrentPage - 1);
anchor.Attributes["class"] = "prev button";
ph.Controls.Clear();
ph.Controls.Add(anchor);
As you can see by the amount of code needed for what is essentially supposed to be be a simple and light-weight anchor, it's not the most optimal solution. I know I could use a Literal but I figured this was cleaner as I'm adding more than one anchor.
I would be interesting in knowing WHY ASP.Net takes over and tries to fix my URL, though.
Why do you have runat="server" and no ID defined? Do you need to access it server side? If you remove the runat="server" everything will work as expected.
For more information regardinging how ASP.NET handles paths check out this MSDN article.
Edit: You can get around the problem then by using a Literal control and then outputing the raw <a href... to it.
Eg:
<asp:Literal ID="myLiteral" runat="server" />
myLiteral.Text = "link text";
Then you can set the visible property on the Literal however you want.
I know this is a bit of an old topic, but I was running into this problem as well and in the end went with a similar solution, but was able to save a few lines of code by doing this in the ascx:
<anchor id="myAnchor" runat="server" href="xxx">link text</anchor>
Then in the code behind, I referenced it using an HtmlGenericControl and can then do this:
myAnchor.TagName = "a";
// other properties set as needed
Anyway, I thought I'd post in case anyone else stumbles in here with the same issue.
Best bet is to make everything app root relative using the magic ~/ lead-in to the url. That tends to keep stuff straight.
There isn't a great answer to your question. ASP.NET is going to treat a relative path in a UserControl as relative to the path of the user control.
What you can do is in the code behind for your user control, set the HRef property of your anchor tag based on the Request.Path property. Then you can create URLs relative to the page.
Alternative is to use a literal like Kelsey was suggestion, or I would just try and map everything app relative with ~/ like Wyatt suggested.
Even a literal doesn't work using ICallBackEventHandler and RenderControl at least... I ended up hacking the tag back client-side :/ e.g in JQuery:
$('#munged_theId').attr('href', './?pg=1');
Ok, we had a problem come up today at work. It is a strange one that I never would have even thought to try.
<form id="form1" runat="server" method="post" action="Default.aspx?id=<%= ID %>" >
Ok, it is very ugly and I wouldn't have ever tried it myself. It came up in some code that was written years ago but had been working up until this weekend after a bunch of updates were installed on a client's web server where the code is hosted.
The actual result of this is the following html:
<form name="form1" method="post" action="Default.aspx?id=<%= ID %>" id="form1">
The url ends up like this:
http://localhost:6735/Default.aspx?id=<%= ID %>
Which as you can see, demonstrates that the "<" symbol is being encoded before ASP.NET actually processes the page. It seems strange to me as I thought that even though it is not pretty by any means, it should work. I'm confused.
To make matters worse, the client insists that it is a bug in IE since it appears to work in Firefox. In fact, it is broken in Firefox as well, except for some reason Firefox treats it as a 0.
Any ideas on why this happens and how to fix it easily? Everything I try to render within the server control ends up getting escaped.
Edit
Ok, I found a "fix"
<form id="form1" runat="server" method="post" action='<%# String.Format("Default.aspx?id={0}", 5) %>' >
But that requires me to call DataBind which is adding more of a hack to the original hack. Guess if nobody thinks of anything else I'll have to go with that.
ASP.NET 3.5 added the "Action" property to the HtmlForm control. Your previous code worked just fine because "action" was just a string, and the code nugget would emit the additional data for you. Now that there is an Action property, you can't use a simple code emit nugget, since a server-side control expects a property to have a literal string value (same as any other server-side control property).
Your workaround of using the biding syntax is correct. To make it work like it used to, you would have to remove the runat=server tag on your form, which would then prevent the ASPX parser from treating it as an HtmlForm control, and instead treat it as a literal (where your code emit nugget would be allowed to work).
Your other option, which may be much cleaner - is to simply set the Form's action property through code-behind in the page_load. The reason the action property is set the way it is, was because in earlier versions of .NET Framework, there was no support for setting the Action property.
your form needs a runat=server
see here this error - http://validator.w3.org/check?verbose=1&uri=http%3A%2F%2Fwww.sitecore.net%2F
runat="server" is asp.net server control syntax. It must not come in html. It is interpreted by ASP.NET. you must remove this attribute.
Possible Reason for this:
1. I think the template is dynamically created. the developer make static site and cut copy paste on server side to make it dynamic but use control as response.write and forgot to remove runat="server" because it must be html content in response.write.
NOTE: No ASP.NET server control gives runat="server" in HTML. It is hardcoded in your code. remove this from both anchor and image tag.
Er... remove the attributes? They aren't valid HTML, and they're only meaningful when interpreted by ASP.NET.
Your pages should not be rendered with runat="server", so something's definitely going wrong here. What does the part of your aspx look like, that corresponds to one of the elements that is giving this validation error?
It seems everyone is doing this (in code posts etc.)...but I don't know how. :(
Whenever I try to manipulate an asp element using JavaScript I get an "element is null" or "document is undefined" etc. error.....
JavaScript works fine usually,...but only when I add the runat="server" attribute does the element seem invisible to my JavaScript.
Any suggestions would be appreciated.
Thanks, Andrew
What's probably happening is that your element/control is within one or more ASP.NET controls which act as naming containers (Master page, ITemplate, Wizard, etc), and that's causing its ID to change.
You can use "view source" in your browser to confirm that's what's happening in the rendered HTML.
If your JavaScript is in the ASPX page, the easiest way to temporarily work around that is to use the element's ClientID property. For example, if you had a control named TextBox1 that you wanted to reference via JS:
var textbox = document.getElementById('<%= TextBox1.ClientID %>');
Making an element runat="server" changes the client-side ID of that element based on what ASP.NET naming containers it's inside of. So if you're using document.getElementById to manipulate the element, you'll need to pass it the new ID generated by .NET. Look into the ClientId property to get that generated ID...you can use it inline in your Javascript like so:
var element = document.getElementById('<%=myControl.ClientID%>');
If you have a textbox:
<asp:TextBox id="txtText" runat="server" />
YOu can use:
var textBox=document.getElementById('<%=txtText.ClientID %>');
Any WebControl exposes the same ClientID property.
All though the question has been answered, thought I would just post some further info...
Rick Strahl provided quite an intresting work around to this problem.
http://www.west-wind.com/WebLog/posts/252178.aspx
Thankfully when ASP .NET 4.0 arrives, it will allow you to specify exacly what the client ID's will be!
http://www.codeproject.com/KB/aspnet/ASP_NET4_0ClientIDFeature.aspx