accessing web.config key from BL and DAL layer?

Hi

I have 3 layers:
WEB APP
BLL
DAL

I have the error log system path stored in web.config

I now want to use this app key in the BLL and DLL logic layers to write to log files when an error occurs
i.e. on catching exeption:

myNS.ErrorLog.clsError.RegisterErrorInLogFile(System.Configuration.ConfigurationManager.AppSettings["ErrorPath"].ToString(), "DAL_MyAccount.cs", "UpdateScheduledReportData()", ex.Message);

Open in new window



however, it error on
System.Configuration.ConfigurationManager.AppSettings["ErrorPath"]
as its in a different project

any ideas what code i need?
websssAsked:
Who is Participating?
 
Carl TawnConnect With a Mentor Systems and Integration DeveloperCommented:
You need to switch those two lines around.  If you re-throw the exception first then the case block exits and the second line will never execute:
catch (Exception ex)
{   
    // this line needs to go first
    MyNS.ErrorLog.clsError.RegisterErrorInLogFile(System.Configuration.ConfigurationManager.AppSettings["ErrorPath"].ToString(), "DAL_MyAccount.cs", "UpdateScheduledReportData()", ex.Message);
    throw ex;
}

Open in new window

0
 
Vel EousResearch & Development ManagerCommented:
In the traditional n-layer architecture, logging is a cross-cutting concern (i.e. it has no particular home as it is shared functionality) and is therefore in an assembly of its own (maybe with other cross-cutting concerns such as policy settings) which is then referenced by your other layers.

Your "logging" would have all the configuration settings it needs, the other layers would just call the functions in that layer and everything should play nicely.
0
 
Carl TawnSystems and Integration DeveloperCommented:
Alternatively you would give you Web layer a means to initialise the BLL from the config, rather than the BLL needing direct access to it.

What exception are you getting? If your BLL is a class library you will have to manually add a reference to the System.Configuration assembly.
0
 
Richard LeeSoftware EnthusiastCommented:
I have used a very nice approach when accessing web specific settings within the other layers of your application. If you are using an IoC container then great, if not, you definitely need to start using one within your application.

This example is detailed in the following article and simply maps a dictionary of key/value pairs to an interface. That interface instance will then be passed to your other layers through dependency injection.

http://blog.mirajavora.com/elegant-app-settings-factory/

The great things about the appSettings is that it is exposed in .NET code as a dictionary, hence it works perfectly in this situation.
0
 
websssAuthor Commented:
Thanks

I've tried the system.configuration in the .cs file
now i'm getting the following
"Unreachable Code Detected" on the "MyNS" word

 catch (Exception ex)
            {
                throw ex;
                MyNS.ErrorLog.clsError.RegisterErrorInLogFile(System.Configuration.ConfigurationManager.AppSettings["ErrorPath"].ToString(), "DAL_MyAccount.cs", "UpdateScheduledReportData()", ex.Message);

            }

Open in new window


I've got the NS added to references  folder
MyNS.ErrorLog

and i'm also
using MyNS.ErrorLog;
at the top of the file!?
0
All Courses

From novice to tech pro — start learning today.