When I deploy my ASP.NET web app to production, I use a config transform to remove debug="true" from <compilation>. However, just today I noticed another section in the web.config that looks like this:
<system.codedom>
<compilers>
<compiler compilerOptions="/define:Debug=True" />
</compilers>
</system.codedom>
What is this? Is the fact that that's there defeating the purpose of removing it from <compilation>? What happens if I remove that attribute as shown above?
Is the fact that that's there defeating the purpose of removing it from
<compilation>
From MSDN C# Compiler Options
To open the debug the flag on the compiler is the /debug not the /define:Debug=True
/debug : Instruct the compiler to emit debugging information.
/define : Defines preprocessor symbols.
So when you define the Debug=True you only make true this case of code:
#if DEBUG == true
// Compile what is inside here !
#endif
the /define:Debug=True is not add any additional debug informations, unless you have include them manual with the above code.
I use the following code to make tests and see whats happens.
txtDebug.Text = HttpContext.Current.IsDebuggingEnabled.ToString();
#if DEBUG
txtDebug.Text += "<br>defined Debug is on";
#endif
#if DEBUG == true
txtDebug.Text += "<br>defined Debug = true is on";
#endif
Now if the debug="false" and with compilerOptions="/define:Debug=True" the results are
false
defined Debug = true is on
if the debug="true" and compilerOptions="/define:Debug=True" the resuls are
true
defined Debug is on
defined Debug = true is on
Now I make one more test, I add this line on web.config
<compiler language="c#;cs;csharp" extension=".cs"
compilerOptions="/define:Debug=True /D:DEBUG,TESTFLAG"
type="Microsoft.CSharp.CSharpCodeProvider, System,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
warningLevel="4" />
And the results are with debug=false
False (debug is false)
defined Debug is on (but the defined DEBUG now is runs)
defined Debug = true is on (This is also runs)
test flag (but the defined extra flag is also runs)
Looking at the MSDN for the /define (Preprocessor Definition) I look that the declaration
/define:Debug=True
is work only for this case of code
#if DEBUG == true
txtDebug.Text += "<br>defined Debug = true is on";
#endif
#if DEBUG. I cannot get this to return false unless I change the configuration dropdown at the toolbar (where you see Debug, Release, etc) and then rebuild. Also, what is the difference between #if DEBUG and #if DEBUG == true? Lastly, what is your final, objecting answer? David Ebbo's answer states that having /define:Debug=True is the same thing as debug="true". Does your answer agree with or contradict his answer?
debug="true" is not the same as /define:debug=true because have higher priority and the define is not working here for that, and I have made a test page and show the results here that proves it. Now I have also in the answer what is the difference between #if DEBUG and #if DEBUG == true, if you see the test you understand them. I can not write them here again.
The string you set in compilerOptions is basically a piece of command line that gets added to all compilations.
If you use aspx pages, you can also set it in there so it only applies to one page. e.g.
<%@ Page Language="C#" CompilerOptions="etc..." %>
How did you end up with it set to "/define:Debug=True" in your config? It is not typical to have that. But to answer your question, yes, this will effectively turn on Debug regardless of the value of the debug attribute.
Unless you have a good reason to have it, I would yank it altogether.
