views:

585

answers:

5

I have a custom server control with a property of Title. When using the control, I'd like to set the value of the title in the aspx page like so:

<cc1:customControl runat="server" Title='<%= PagePropertyValue%>' >
more content
</cc1:customControl>

When I do this, however, I am getting the exact String <%= PagePropertyValue%> being displayed rather than the Property Value that I would like to see.

So after trying the databinding expression (as suggested below). I don't get the string literal that looked bad but I don't get anything else either.

<cc1:customControl runat="server" Title='<%# PagePropertyValue%>' >
more content
</cc1:customControl>

What do I need to do to my custom control to take this sort of value? Or is there something I need to do to the page.

+1  A: 

Try using databinding syntax: <%# PagePropertyValue %>

Zachary Yates
That made it display blank rather than the actual code string. I am not implementing a databinding event on my control. I get similar results with an asp label control with both settings. (using text property).
Jeff Martin
Try call label.DataBind() and it should display whatever the expression returns.
Tom Jelen
+6  A: 

You cant. <%= %> will write the string directly to the response-stream, which happens after the server control is constructed. See this post for an explanation.

So its either codebehind, or <%# + databinding as Zachary suggests.

Tom Jelen
+1  A: 

For the bind property value to work correctly as suggested, you will have this in the aspx or ascx file :

<cc1:customControl runat="server" Title='<%# PagePropertyValue %>' >
more content
</cc1:customControl>

You will then need to actually bind data in your page wich you have to add this in you code behind file (code in C#)

protected void Page_Load(object sender, EventArgs e)
{
    DataBind();
}

That way it will bind the data in your ascx or aspx file.

lucian.jp
+1  A: 

As a followup to my own question, I have discovered that what I really wanted was to use ASP.NET Expressions using the <%$ syntax, since what I wanted to do was put in localized content.

This can be done with apparently no extra handling on the server control side.

<cc1:customControl runat="server" Title='<%$ Resouces: ResourceFile, ContentKey %>' >
more content and controls
</cc1:customControl>

This works just fine.

Jeff Martin
A: 
Jonx