Can I get parameter names/values procedurally from the currently executing function?

I realize people linked to other questions which mentioned PostSharp, but I couldn’t help posting the code that solved my problem (using PostSharp) so other people could benefit from it.

class Program {
    static void Main(string[] args) {
        Trace.Listeners.Add(new TextWriterTraceListener(Console.Out));
        new MyClass().MyMethod(44, "asdf qwer 1234", 3.14f, true);
        Console.ReadKey();
    }
}
public class MyClass {
    public MyClass() {
    }
    [Trace("Debug")]
    public int MyMethod(int x, string someString, float anotherFloat, bool theBool) {
        return x + 1;
    }
}
[Serializable]
public sealed class TraceAttribute : OnMethodBoundaryAspect {
    private readonly string category;

    public TraceAttribute(string category) {
        this.category = category;
    }

    public string Category { get { return category; } }

    public override void OnEntry(MethodExecutionArgs args) {
        Trace.WriteLine(string.Format("Entering {0}.{1}.", 
                                      args.Method.DeclaringType.Name, 
                                      args.Method.Name), category);

        for (int x = 0; x < args.Arguments.Count; x++) {
            Trace.WriteLine(args.Method.GetParameters()[x].Name + " = " + 
                            args.Arguments.GetArgument(x));
        }
    }

    public override void OnExit(MethodExecutionArgs args) {
        Trace.WriteLine("Return Value: " + args.ReturnValue);

        Trace.WriteLine(string.Format("Leaving {0}.{1}.", 
                                      args.Method.DeclaringType.Name, 
                                      args.Method.Name), category);
    }
} 

Simply adding the Trace attribute to a method will cause very nice debugging information to be output, like so:

Debug: Entering MyClass.MyMethod. 
x = 44
someString = asdf qwer 1234
anotherFloat = 3.14
theBool = True
Return Value: 45
Debug: Leaving MyClass.MyMethod.

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