How do i get rid of __o is not declared?
I have some code in my master page that sets up a a hyperlink with some context sensitive information
<%If Not IsNothing(Profile.ClientID) Then%>
<span class="menu-nav">
<a target="_blank"
href=
"http://b/x.aspx?ClientID=<%=Profile.ClientID.ToString()%>&Initials=<%=Session("Initials")%>"
>
Send
<br />
SMS
<br />
</a>
</span>
<%End If %>
<span class="menu-nav"> <!-- Name __o is not declared Error is flagged here-->
Now the issue seems to be in the href part. If I remove the dynamic code the error disappears. Can anyone tell me how to resolve this issue?
Solution 1:
I've found the answer on the .net forums. It contains a good explanation of why ASP.Net is acting the way it is:
We have finally obtained reliable repro and identified the underlying issue. A trivial repro looks like this:
<% if (true) { %> <%=1%> <% } %> <%=2%>
In order to provide intellisense in <%= %> blocks at design time, ASP.NET generates assignment to a temporary __o variable and language (VB or C#) then provide the intellisense for the variable. That is done when page compiler sees the first <%= ... %> block. But here, the block is inside the if, so after the if closes, the variable goes out of scope. We end up generating something like this:
if (true) { object @__o; @__o = 1; } @__o = 2;
The workaround is to add a dummy expression early in the page. E.g. <%="" %>. This will not render anything, and it will make sure that __o is declared top level in the Render method, before any potential ‘if’ (or other scoping) statement.
An alternative solution is to simply use
<% response.write(var) %>
instead of
<%= var %>
Solution 2:
Yes, I have experienced the same bug occasionally in pages that use server side constructs on ASPX pages.
Overtime, I found a fix for it (I'm sorry, I just haven't been able to find out where I found this bit of info again.) and that fix is to put the following code above the errant <%...%>
block:
<%-- For other devs: Do not remove below line. --%>
<%="" %>
<%-- For other devs: Do not remove above line. --%>
Apparently, where you put the above code makes all the difference to VS.NET, so it may take a few tries to get it right.
Solution 3:
This is an odd solution, but for me I managed to fix this problem by simply closing the offending open files in Visual Studio.
With them open, i was erratically getting the __o problem.
As soon as I closed them, the __o problem disappeared.