I need to initialize the text attribute of the text box element with a property from some where else when actually I can simply do this from code but it will be much m
OK so the basic problem here is that if you use an inline expression you can NOT use it to set a property of a server-side control outside of a binding context (using a binding expression). I have inferred that this is probably because of the timing of the evaluation of these inline expressions. You can, however, render client-side markup in this way. If you want to keep the functionality purely in your aspx file, this is the way to do it.
Edit: Based on input from Justin Keyes, it appears it IS possible to use a binding expression to set the property. You need to manually invoke Page.DataBind()
to trigger the textbox to evaluate the expression (see answer below).
For instance this:
Will produce this output:
<%= Now.ToShortDateString() %>
On the other hand this:
<%= "" & Now.ToShortDateString() & ""%>
Will produce this output:
7/27/2011
The "normal" way to solve this problem is just to set the Label.Text
properties in a Page.Load
event handler or another appropriate event handler depending on your needs, as below. This is the way I believe most people would prefer to do it, and is most easily understandable in my opinion.
Markup:
Code:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
lbl.Text = Now.ToShortDateString()
End Sub