c# writing to the event viewer

Question

I\'m trying to write to the event viewer in my c# code, but I\'m getting the wonderful \"Object reference not set to an instance of an object\" message. I\'d appreciate som

Answer 1

Here's how I implemented Event logging. I created a generic ILogger interface so I can swap in different logging mechanisms:

interface ILogger
{
    void Debug(string text);

    void Warn(string text);

    void Error(string text);
    void Error(string text, Exception ex);
}

My implementation class is very simple:

class EventLogger : ILogger
{
    public void Debug(string text)
    {
        EventLog.WriteEntry("MyAppName", text, EventLogEntryType.Information);
    }

    public void Warn(string text)
    {
        EventLog.WriteEntry("MyAppName", text, EventLogEntryType.Warning);
    }

    public void Error(string text)
    {
        EventLog.WriteEntry("MyAppName", text, EventLogEntryType.Error);
    }

    public void Error(string text, Exception ex)
    {
        Error(text);
        Error(ex.StackTrace);
    }
}

Note that I do not instantiate EventLog. To use my logger class I just have the following reference (you could have this returned by a static factory method):

private static readonly ILogger log = new EventLogger();

And the actual usage is like this:

try
{
    // business logic
}
catch (Exception ex)
{
    log.Error("Exception in MyMethodName()", ex);
}