Need Help creating a custom attribute in C#

EDN Admin · Dec 23, 2007

Hello,
I need to create a custom attribute class that will help me log the beginning and completion of a method, as well as any error of type Exception.

Ideally, it will look something like this

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle>[Loggable(OnStart=true, OnEnd=true, OnError=false)]
pubilc class A
{
<blockquote dir=ltr style="margin-right:0px
public void DoSomething() // Inherits logging attribute from class
{
<blockquote dir=ltr style="margin-right:0px
// ... </blockquote>
}

[NotLoggable]
public void DoSomethingElse() // Doesnt log, or equivalent to [Loggable(OnStart=false, OnEnd=false, OnError=false)]
{
<blockquote dir=ltr style="margin-right:0px
// ... </blockquote>
}

[Loggable(OnError=true)] // Inherits from class, except OnError=true.
{
<blockquote dir=ltr style="margin-right:0px
// ... </blockquote>
} </blockquote>
}


I know how to define a custom attribute (have a book). What Im not sure is about methods/properties inheritting an attribute from their classes.

Also, I need to actually do something with the attributes (log), so what I basically need is to provide for an action to occur before running a method (i.e. log the method name, parameters and start time), after the method returns (log the method name, return value if any, and end time), and if the method throws an exception, log it, the errorMessage and stack-trace.
It should be equivalent to this:

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle>try
{
<blockquote dir=ltr style="margin-right:0px
LogBegin(method name, parameters[], DateTime.Now);
retVal = DoSomething(paramaters[]);
LogEnd(method name, retval, DateTime.Now); </blockquote>
}
catch (ApplicationException ex)
{
<blockquote dir=ltr style="margin-right:0px
// Do not log this - it is less important
// ... </blockquote>
}
catch (Exception ex)
{
<blockquote dir=ltr style="margin-right:0px
// Log this
LogError(method name, ex.Message, ex.type, ex.stackTrace); </blockquote>
}



Is this possible? I assume this isnt much different from a Transaction attribute.
I dont want some one to write my code for me, of course, but a tip on how to do this, or an example I can use to extrapolate my code would be greatly appreciated.

Thanks,
Assaf.




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Need Help creating a custom attribute in C#

EDN Admin

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