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Question

Inline script does not resolve in ASP.Net custom control

Answer 1

A:

Values in a web control do not render server side code. Rather set that from the Code Behind

RegExValidator1.ValidationExpression = RegExStrings.SomePattern;

WebDude 2008-10-22 11:28:06

This doesn't make sense as this style of inline script is used all the time for databinding within web controls.

Josh 2008-10-22 11:53:58

If you could provide some documentation confirming this then I would be a little less skeptical. I know I can set this in the codebehind, but I shouldn't have to.

Josh 2008-10-22 11:54:44

Answer 2

A:

It's being taken as a literal string, try

ValidationExpression='<%= RegExStrings.SomePattern %>'

Edit: The above doesn't work, I've tried to see how to do this without success,I usually set properties in the code-behind and only use this syntax for databinding when I have to. I'd be interested to know if it can be done too.

PhilGriffin 2008-10-22 11:30:29

This isn't the problem. Regardless of whether I put a single quote or a double quote doesn't matter. ASP.Net uses everything inside of the <% %> operators as server side code.

Josh 2008-10-22 12:04:04

Answer 3

A:

If your regular expression validator has the runat="server" attribute, then change it from the code behind. It would be much easier.

Sir Psycho 2008-10-22 13:02:39

Answer 4

+1 A:

But why is this? I can reproduce your problem using a simple aspx page as below:

<%@ Page language="c#" AutoEventWireup="true" %>
<html>
  <body >
    <form id="Form1" method="post" runat="server" action="?<%=Request.QueryString%>">
                Query String value: <%=Request.QueryString %>
                <br />
                <input type=submit />
     </form>
  </body>
</html>

This displays the following after submitting the form:

Query String value: %3c%25=Request.QueryString%25%3e

For some reason, the inline code is not executed when the runat="server" is present. The strange thing is I have 3 machines that do not behave this way and one that does, so I can only assume that this is an IIS/.NET config issue, possibly caused by a recent MS Update. The software I have installed recently on the machine exhibiting this behaviour is: Visual Studio 2008 WSE 3.0 IE8 RC1

I wonder if any of these have caused this?

MarkD 2009-01-28 14:36:38

Thanks for your thorough investigation into this matter :) Honestly I had given up on this one, but you seem to be pretty determined. Also, hopefully the rep boost will help you out a little too ;)

Josh 2009-01-30 02:09:00

Answer 5

A:

You're using a databinding expression on a control that is not databound. You need to call DataBind(), or use an ExpressionBuilder implementation. A simple ExpressionBuilder for binding to arbitary code can be found at http://weblogs.asp.net/infinitiesloop/archive/2006/08/09/The-CodeExpressionBuilder.aspx

devstuff 2009-01-28 15:03:30

Answer 6

+1 A:

devstuff, that doesn't explain why this works on 3 of my machines, but not a 4th one, does it? They are all using the same .NET Framework version and IIS settings (I believe, having checked as many as I coukd)

MarkD 2009-01-28 15:24:54

Answer 7

+1 A:

I've uninstalled the .NET framework while investigating this (3.5 then 3.0 and 2.0) - I then had no problems after Installing each of the following: .net framework 2.0 .net framework 2.0 SP1 .net framework 3.0 .net framework 3.0 SP1 .net framework 3.5

But after I installed .net framework 3.5 SP1 the behaviour returned – I guess this is the issue. I have raised this with Microsoft and will update this thread when I get a response.

MarkD 2009-01-29 12:23:59

Answer 8

+2 A:

This has now been cleared up my MS. The issue I discovered was caused by the fact that the "action" attribute in server forms had no effect prior to .NET 2 SP2, but now can be set. Code render blocks have never worked in attribute values - this is explained towards the end of this post.

This was a consequence of a deliberate change in behaviour introduced in Microsoft .NET Framework 3.5 SP1. Prior to the service pack, action and method attributes on server side FORM tags could not be over-ridden. If specified they would be replaced by ASP.NET with "POST" and "page name".

Previously, the ASP.NET page parser did not prevent one specifying these attributes although the documentation advised against it for the action attribute: http://msdn.microsoft.com/en-us/library/k33801s3.aspx

In particular the comment (in the context of the FORM element):

• "The opening tag must not contain an action attribute. ASP.NET sets these attributes dynamically when the page is processed, overriding any settings that you might make. "

The issue that was originally reported by Josh, where the code block was not being interpreted is not new behaviour but is a known bug - code render blocks cannot be used within server control attributes. This is reported as a "Connect" bug: http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=109257 which contains the following: " Attributes of server controls cannot take an inline expression as value. This explains the unexpected behaviour as seen with: " <link href="<%=RootPath %> ..." However, inline code can be used for values of attributes."

MarkD 2009-02-19 10:00:37

Awesome investigation on this one Mark! I really appreciate the work you did on this issue.

Josh 2009-02-19 15:09:37

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Inline script does not resolve in ASP.Net custom control

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