What I want to do is something like this:
<asp:Label ID="titleLabel" runat="server"
**Text='<%# SiteMap.CurrentNode.Title %>'**></asp:Label>
Where I can bind the name of the current page node in the Site Map to the title label on that page. We are doing this because, until we get these names finalized, they may change often. The above code does not work, at least for me; it displays nothing.
Any ideas are appreciated.
EDIT: Obviously I could do this in the code behind (i.e. Page Load event or something similar) but I would really rather do it in the aspx code.
It does work with
<span><%= SiteMap.CurrentNode.Title %></span>
which is the same output as asp:Label
As an alternative to using a label, you could also use the SiteMapPath control and hide the parent nodes:
<asp:SiteMapPath ID="SiteMapPath1" runat="server" ParentLevelsDisplayed="0">
The property ParentLevelsDisplayed allows you to specify how many parent nodes of the current sitemap node you want to display.
Its been a while but I believe its <%= #Eval(SiteMap.CurrentNode.Title) %>
Edit:
Text='<%= SiteMap.CurrentNode.Title%>'
Hopefully that works the same as it would <%= SiteMap.CurrentNode.Title%>.
Related
When working with markup if I want to include some content conditionally, I use a placeholder in a normal way:
<asp:Placeholder Visible=<%# IsExpired %>
<span>Prolong your subscription</span>
</asp:PlaceHolder>
Also I can use if-directive:
<% if(IsExpired) {%>
<span>Prolong your subscription</span>
<% }%>
I prefer using the first one just because it does not make my markup messy. And what's the best way to conditionally include content? From the performance point of view, are they similar?
native HTML tags are always faster than rendering server controls as there is no time spent for rendering them
I think there is hardly anything to do with performance whether way you choose here. But actually you may use the following code:
<asp:Label runat="server" Visible=<%# IsExpired %>
Prolong your subscription</asp:Label>
instead the other two. This could make it look more straight-forward.
I'd never use C# code in Web Forms view. In addition I will avoid setting the Visible property in the markup and I will set it in the code behind on some event.
phWhatever.Visible = IsExpired;
Quite often you can avoid creating the IsExpired property.
Of course what #Johnny suggested is correct. If you need to hide what is effectively only one control you hide the control directly.
I'm outputting a few lines of Javascript within a Repeater control on an ASPX page. I want to use a value from my DataSource inside the script tag.
A very basic example might be:
<asp:Repeater ID="RepeaterBlah" runat="server">
<ItemTemplate>
Hello <%# DataBinder.Eval(Container.DataItem, "SomeName")%>
<script>myfunction(<%# DataBinder.Eval(Container.DataItem, "SomeNumber")%>)</script>
</ItemTemplate>
</asp:Repeater>
I'm aware that most people won't repeat script tags like this, but I am using a small snippet of code from a third-party that you can place anywhere on a page to create a Flash object. You pass it a number so it knows which image gallery to display. No problems using several on one page.
To begin with, this worked fine, although I noticed the colours in Visual Web Developer indicated that it didn't really like the <%# being used inside a <script> tag. Intellisense was going a bit nuts in the code-behind too!
So what is the correct way to pass Dataset items into a script tag?
This perhaps? (Can't quite remember if the + signs should in fact be & signs though)
<%# "<script>myfunction(" + DataBinder.Eval(Container.DataItem, "SomeNumber") + ")</script>" %>
Another alternative syntax would be the following:
<%# Eval("SomeNumber", "<script>myfunction({0});</script>") %>
This uses the optional parameter where you can supply a format string.
In my own server control, I would like to implement something similar to the ListView:
<asp:ListView runat="server">
<LayoutTemplate>
<asp:PlaceHolder runat="server" id="itemPlaceholder" />
</LayoutTemplate>
</asp:ListView>
I have created an ITemplate property, I can set the layout in the aspx page, and I am doing ITemplate.InstantiateIn(myControl).
But I can't figure out how to insert controls at the placeholder. I'm guessing it would be something like MyTemplate.FindControl("itemPlaceholder").Controls.Add(myControl). I tried casting to the type of my ITemplate, but I get the error:
Unable to cast object of type 'System.Web.UI.CompiledTemplateBuilder' to type 'MyNamespace.MyLayoutTemplate'
What am I missing?
Edit: I just found this: http://www.nikhilk.net/SingleInstanceTemplates.aspx Control developers can define templates to be single instance using metadata which causes the ID'd controls within the template contents to be promoted to the page level... The parser and code-generator together work behind the scenes to add member fields, and initialize them at the right time.. It seems to be only for user controls? I tried Page.FindControl() after doing this but it didn't find anything.
Ok, this was simply a matter of user error. I instantiated the ITemplate in a Panel, so obviously Page.FindControl() (which is not recursive) wouldn't work. Once I did Panel.FindControl(), everything worked.
In the past I have used this library with sucess
http://www.denisbauer.com/ASPNETControls/DynamicControlsPlaceholder.aspx
I'm a bit new to .Net development, been working in Java for some time now. I have an aspx page and we need to externalize some strings to make it more flexible.
If I have a table somewhere and there is just a string sitting outside an asp tag, I can replace it so that
<th> Specific Foo String </th>
becomes
<th> <%= Strings.foo %> </th>
and everything is fine, the problem I'm running into is how do you do this kind of interpolation on an asp tag property
I tried changing
<asp:Label runat="server" ID="lblFoo" Text="Specific Foo String Entry" />
to
<asp:Label runat="server" ID="lblFoo" Text='<%= Strings.foo %> Entry' />
and
<asp:Label runat="server" ID="lblFoo" Text='<%#Eval("Strings.foo") %> Entry' />
but neither worked. Is what I'm doing not possible in the aspx file, I know that I can simulate this by rewriting their properties in the code behind, but that's a level of overhead I'd rather not deal with.
Thanks
I think you are looking to do this:
<asp:Label runat="server" id="label1" Text='<%# Strings.Foo + " Entry"%>' />
Then in your code behind (most likely in your OnPageLoad) you need to call
if(!Page.IsPostBack) Page.DataBind();
You need to be cautious however as calling DataBind on controls like textboxes or any labels that may have changed due to logic in the code behind will have their values overwritten with the bound values. Checking that you are not on a post back can help with this, but there are still gotchas.
Also note that I had to move the " Entry" text into the binding statement. If it is placed outside the last '%>' then the binding does not work and it will spit out:
<%# Strings.foo %> Entry
In the codebehind of the page you would do this:
lblFoo.Text = Strings.foo + " Entry";
A good place to put this code would be in the overriden OnLoad method but that is simply a suggestion as I am unfamiliar with your application and the life cycle needs of your page.
If you want to do all this in the aspx page then simply do this:
<span><%= Strings.foo %> Entry</span>
as a Label renders as a span anyhow.
If your objective is an HTML table of strings, then you can create either a ListView or a GridView and DataBind to that. It would save you the trouble of writing out all of your properties and will also produce the correct table tags for the data.
Without knowing more about your data, I cannot provide a detailed code snippet.
You're talking about resources. Read Basic Instincts Resources and Localization in ASP.NET 2.0 which shows you the built in resource editor, and how to use the "<%$ ... %>"-binding, or using meta:resourceKey attribute.
I have a Repeater which displays a list of items (in a grid-like/table view). When a user clicks an item, I display an UpdatePanel under this item with additional information relevant to the item (similar to Accordion control). I know how to populate the elements of the UpdatePanel in code-behind (I pass the ID of the selected element in the Repeater control as CommandArgument, get additional info for this ID, and set up the text fields of the active UpdatePanel controls). But I'm wondering if I could set up binding directly in the ASPX (instead of code-behind). When I used the <%= %> syntax to assign text fields of the UpdatePanel control the values of the page properties, e.g. <%= Comment %>, it sort of worked, but it changed the fields of all UpdatePanels in the repeater. Is there any way to bind the active UpdatePanel to the current values and leave already bound UpdatePanels unchanged?
Are you looking to display a container that displays additional information? Is there other activity in the "box" that requires it be an updatepanel?
<asp:repeater>
<itemtemplate>
<%# Eval("Name") %> <%# Eval("LastName") %><br />
<span onclick="$get('<%# Eval("Id") %>')">View Age</span>
<div id="<%# Eval("Id")%>" style="display:none;">
Age: <%# Eval("Age") %>
</div>
<itemtemplate>
</asp:repeater>
Ithink that's right, some syntax may be off a bit (typing without intellisense). Would that work?
I used ID as a unique identifier for the div id and the onclick command. You could also use jquery, asp:controls or whatever else you wanted.
Easiest way is to nest a FormView inside the update panel. Then the only thing you need to do in the code behind is get the additional info, assign it to the FormView.DataSource, and call FormView.DataBind(). Everything in the FormView will use the <%# Eval("SomeColumn") %> syntax. You'll probably need to use a FindControl() to get a reference to the FormView. I'd type up the code for you but I'll save you some headaches down the road and say DON'T DO THIS.
The update panel is about the most inefficient way to do any ajax stuff. The only way to get it all to wire up correctly with this repeater and server side code is to either have a gigantic viewstate or to rebind the repeater in your page load. You are turning a request that could be 300ms into something that will take over a second...or longer! Get familiar with a good ajax framework and don't be afraid to write real html. At the very least, use a webservice that loads a usercontrol with your markup.
I know the update panel is easy, and it's built in. It might even be adequate for what you are doing, but you must resist. You'll be glad you did.