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Embedded code (<%= %>) in button control

I'm working on a project where I'm using the <%= getString("key")%> to dynamically get the appropriate text.
this works great when i use it in simple p tags, but i can't find a way to do this with controls like Button/Label etc.
Is there any way, other than calling
Mybutton.Text = getstring("key");
to dynamically add the text?
The idea is that getString retrieves af language code, and depending on that code gets a string in the appropiate language.
I've been looking around, but all i come across is using the embedded code tags directly in the aspx pages, which wont cut it for buttontext.

If you can use DataBinding instead of the <%= operator, you can use:
<asp:Button ID="MyButton" Text='<%# getstring("key") %>' />
This is a good explanation of why <%= won't work in this context.

OnClientClick event doesn't register javascript alert from code-behind

Alright, I have an embarrassingly simple question that hopefully has an embarrassingly simple answer. I am trying to get an asp:ImageButton to display an alert message that contains variables from my codebehind. Here's the overly simplified version of the code:
public string AlertMe
{
get
{
return "alert('hi');";
}
}
Now when I try and access it this way:
<asp:ImageButton ID="btn" runat="server" ImageUrl="/Images/img.ico" OnClientClick='<%=AlertMe%>'/>
I see a postback, but no alert message, as if it can't access my property at all. Meanwhile, these 2 lines:
<%=AlertMe%><br />
<a onclick="<%=AlertMe%>">click this</a>
both work fine and dandy. (The first displays the code for the javascript alert, and the second fires the alert with no issues.)
So my big question is: why does the OnClientClick event for an asp control fail to register the alert? Is there an obvious flaw I'm missing, or do I really need to register the entire event from code-behind?

You can't use the <%= ... %> syntax to set attributes of a Server Control. To set dynamic attributes on Server Controls, you have to set it in code.
this.btn.OnClientClick = this.AlertMe;
This is because <%= ... %> is a shortcut for Response.Write(). So, it isn't called until after the aspx has been parsed, evaluated, and rendering has begun. By then it's too late.
As an alternative to setting the value in the code behind, you could use this quasi-declarative technique:
<asp:ImageButton ID="btn" runat="server" ImageUrl="/Images/img.ico" />
<%
btn.OnClientClick = <%=AlertMe%>;
%>
There are other ways to get around it. This answer to a similar question discusses several approaches you can take. I can't find any "official" reference (eg, msdn) that mentions this specifically, but I didn't look that hard. Here are a couple of blog posts that discuss the issue as well:
Blog post by Jim Black: Server tags cannot contain <% ... %> constructs
Blog post at weblogs.asp.net: Use ExpressionBuilder To Avoid “Server tags cannot contain <% … %> constructs”
Or google it with bing for more fun reading.

For anyone else encountering this issue, I ran across this blog from way back when:
http://weblogs.asp.net/infinitiesloop/archive/2006/08/09/The-CodeExpressionBuilder.aspx
I found the sections about Expression Builders and ViewState concerns to be particularly informative.

I think its a quoting problem. Try
OnClientClick="<%=AlertMe%>"

how to access repeater label value in javascript

This is my javascript
function btnEditClick() {
alert(document.getElementById('<%=LblRefPhyID.ClientID %>').value);
}
<asp:Repeater ID="repeaterRefPhysicianList" runat="server">
<ItemTemplate>
<tr onclick="selectRow(this);">
<td class="csstablelisttd" style="display: none;">
<asp:Label ID="LblRefPhyID" runat="server" Text='<%#Eval("Ref_Phy_ID")%>'></asp:Label>
</td>
on clientclick of Edit button i have to pass RefphyId to another page how can i do that..

It's a repeater. That means that the ItemTemplate will be repeated for each item in your databound collection.
This comes with a caveat: IDs are supposed to be unique. So when you say that your asp:Label has an ID of LblRefPhyID, ASP.NET automagically does you the favor of generating unique IDs for each instance of the repeater that eventually makes its way to your generated HTML. These generated IDs will be based on your original value of LblRefPhyID, but it won't be exactly that, so a plain document.getElementById() outside of the repeater won't work.
There are many ways to work around this, and the very first step you need to do is to actually write some code that will take the automatic generated IDs into account. Maybe write some Javascript to cache the IDs using LblRefPhyID.ClientID, maybe do it dynamically onclick, whatever.
EDIT
And, oh yeah, #Pointy is completely correct in stating that label elements don't have values, just their inner HTMLs. I don't get why he got downvoted for giving a correct response.

Try to set css class instead of id and bind elements click event by class name.
I'm using jquery for this:
$(document).ready(function(){
//bind click event on our label class
$('.lblRef').live('click', function(){
alert($(this).text());
});
});
And this in asp.net page code:
<asp:Label CssClass="lblRef" runat="server" Text='<%#Eval("Ref_Phy_ID")%>'></asp:Label>

HTML <label> elements don't have a "value". They do have contents:
alert(document.getElementById('<%=LblRefPhyID.ClientID %>').innerHTML);

Best way would be to check what is the pattern of id generated by the repeater on the client side and then you can use that id to get the value of the label using innerHTML.
For instance in your case id generated may be :
repeaterRefPhysicianList_LblRefPhyID_01 to till the number of rows in source.
So you can use this information with innerHTML to get the value of the label..
All in all just check your html page you will know what to do next :)

How to set HTMLEditorExtender HTML from client side

I cannot get this to work, here is code that I found in another thread but it is not working for me, I'm getting "set_content is not a function" :
$find("<%=Hee.ClientID%>").set_content("whatever");
Is this still valid?
I also tried to set value of the textbox it extends, tried setting InnerHtml of both,none worked.

I was going nuts for hours looking for a way to change the content and here's what I've come up with that works quite well:
This is the TextBox and Extender:
<asp:Textbox ID="replyBody" Height="450px" Width="892px" runat="server" TextMode ="MultiLine" />
<ajaxToolkit:HtmlEditorExtender ID="replyBody_HtmlEditorExtender" runat="server" Enabled="True" EnableSanitization="false" TargetControlID="replyBody">
</ajaxToolkit:HtmlEditorExtender>
Now this is the javascript that changed the value:
<script type = "text/javascript" >
function changeText(someString){
document.getElementById('ctl00_ContentPlaceHolder1_replyBody_HtmlEditorExtender_ExtenderContentEditable').innerHTML = someString;
}
</script>
This works like a charm. The above element ID is actually that of a div, however changing its contents updates the replyBody.Text property

$find("<%= Hee.ClientID %>")._editableDiv.innerHTML = "whatever";

Try this:
$("#<%=Hee.ClientID%>").html("whatever");

You could try this out:
var ctrl = $get("<%=Hee.ClientID%>").control;
ctrl.set_content("whatever");

problem with masterpage and jquery

I have a MasterPage that inside its content section I added a FORM element.
When accessing that page, all my controls are renamed since the FORM is runat=server.
And thus when selecting in jquery, even the form has been renamed
How can I fix that?
thanks

With a master page, all elements will have ct100__etc appended to the ID of the element. This is a feature since its a naming container. Typically, the way to work around it is to use syntax like:
$("#<%= button.ClientID %>").click(..);
To access the longer ID's, or rely on CSS classes to identify elements. Another trick is to wrap certain sections of the form with a DIV HTML element and give it an ID to target.
HTH.

You can't, that's the behavior of .Net. What you can do is adjust your jquery usage to incorporate the ClientID of the controls you're using. The easiest way is to have some sort of translation variable injected into script in the head somewhere.
<script language="javascript">
var myControl1 = '<%=myControl1.ClientID %>';
</script>
Then you can use myControl1 as a string variable to inject the client id into your jquery calls in a more readable fashion.

Have a look at this post here
http://john-sheehan.com/blog/custom-jquery-selector-for-aspnet-webforms/
Explains it all pretty clearly. the trick is to use ClientId

In addition to the .ClientID approach suggested in many of the other answers, you can use jQuery's endswith selector.
eg: Select the element whose id endswith "myid" (eg ctl001_form1_myid)
$('[id$="myid"]');
or if you are using .net 4, you can set ClientIdMode="false" to prevent the renaming.

You can use Control.ClientID for this. Something like
$("#<%= yourelement.ClientID %>")

You can also create a CSSCLASS and then access by $('.classname')
<asp:TextBox id="tb4" Text="Hello World!" cssclass="txtboxtb4" runat="server" />
alert($('.txtboxtb4').val());

Another way is put controls in span tag.
<span id="txt">
<asp:TextBox ID="txt" runat="server"></asp:TextBox>
</span>
Than you can select you element like this in jQuery.
$('#txt > input').val('Hello world');
But my way is, select element with ends with selector.
$('input[id$="txt"]').val('Hello world');
Works for my cases. Hope help.