== Debugging ==

  * Enable WPF debug output. In Visual Studio, Options > Debugging > Output Window > WPF Trace Settings > Data Binding > All.
  * Add a high TraceLevel to your binding: <code csharp>System.Diagnostics.PresentationTraceSources.SetTraceLevel(NewBinding, System.Diagnostics.PresentationTraceLevel.High);</code>
  * Run application, and review log in "Output" tab in Visual Studio.
  * Add ''System.Diagnostics'' entry to ''app.exe.config''.  See:
    * [[swdev:dotnet:debugging|Debugging for .NET]]
    * [[http://www.thejoyofcode.com/System.Diagnostics_hidden_SourceLevels.aspx|The Joy of Code: System.Diagnostics Hidden SourceLevels]] 
    * [[http://msdn.microsoft.com/en-us/library/aa345169.aspx|MSDN: PresentationTraceSources Class]]
    * [[http://msdn.microsoft.com/en-us/library/system.diagnostics.presentationtracesources.settracelevel.aspx|MSDN: SetTraceLevels]]
    * [[http://msdn.microsoft.com/en-us/library/6w20x90k.aspx|MSDN: EventLog.WriteEntry method]]
  * [[http://stackoverflow.com/questions/4026543/is-there-a-good-tool-for-debugging-xamls-databinding-behavior-errors-at-runtim|Tools for Debugging Data Binding at runtime]]
  * [[http://bea.stollnitz.com/blog/?p=52|Bea Stollnitz: How can I debug WPF bindings?]]

== Using System.Diagnostics ==

=== Configuration File ===
Add the following to the ''//app//.exe.config'' file (must reside in the same folder and the ''//app//.exe''):
<code xml>
<configuration>
...
<system.diagnostics>
    <sources>
      <source name="srcMyAppDebug" switchName="SourceSwitch" >
        <listeners>
          <add name="myTextListener" />
        </listeners>
      </source>
    </sources>
    <switches>
      <add name="SourceSwitch" value="All" />
    </switches>
    <sharedListeners>
      <add name="myTextListener"
           type="System.Diagnostics.TextWriterTraceListener"
           initializeData="Debug.txt" />
    </sharedListeners>
    <trace autoflush="true" indentsize="4"></trace>
</system.diagnostics>

</configuration>
</code>

The ''SourceLevels'' used by the ''SourceSwitch'' (''//app//.exe.config'' configuration file) could be any of these:
<code csharp>
public enum SourceLevels
{
    All             = -1,
    Off             = 0,
    Critical        = 1,
    Error           = 3,
    Warning         = 7,
    Information     = 15,
    Verbose         = 31,
    ActivityTracing = 65280,
}
</code>

The listener could also be:
<code xml>
  <listeners>
     <add name="myXmlListener"
          type="System.Diagnostics.XmlWriterTraceListener"
          initializeData= "Debug.xml" />
  </listeners>
</code>

=== Writing Events ===

To write to the event log:
<code csharp>
System.Diagnostics.Trace.TraceInformation("Some operation here: Hello World");
System.Diagnostics.Trace.TraceError("Error: Something failed here.");
</code>

Alternatively, and more flexible:
<code csharp>
TraceSource srcMyApp = new TraceSource("srcMyAppDebug");
srcMyApp.TraceInformation("Some operation here: Hello World");
srcMyApp.TraceEvent(TraceEventType.Error, 0, "Error: Something failed here.");
</code>

The ''TraceEventType'' could be any of these:
<code csharp>
public enum TraceEventType
{
    Critical    = 1,
    Error       = 2,
    Warning     = 4,
    Information = 8,
    Verbose     = 16,
    Start       = 256,
    Stop        = 512,
    Suspend     = 1024,
    Resume      = 2048,
    Transfer    = 4096,
}
</code>

Another example:
<code csharp>
using System.Diagnostics;

private void WriteToEventLog(string message)
{
  string cs = "srcMyApp";
  EventLog elog = new EventLog();

  if (!EventLog.SourceExists(cs))
  {
     EventLog.CreateEventSource(cs, cs);
  }

  elog.Source = cs;
  elog.EnableRaisingEvents = true;
  elog.WriteEntry(message);
}
</code>

Another example (by Microsoft):
<code csharp>
using System;
using System.Diagnostics;
using System.Threading;

class MySample{

    public static void Main(){

        // Create the source, if it does not already exist.
        if(!EventLog.SourceExists("MySource"))
        {
             //An event log source should not be created and immediately used.
             //There is a latency time to enable the source, it should be created
             //prior to executing the application that uses the source.
             //Execute this sample a second time to use the new source.
            EventLog.CreateEventSource("MySource", "MyNewLog");
            Console.WriteLine("CreatedEventSource");
            Console.WriteLine("Exiting, execute the application a second time to use the source.");
            // The source is created.  Exit the application to allow it to be registered.
            return;
        }

        // Create an EventLog instance and assign its source.
        EventLog myLog = new EventLog();
        myLog.Source = "MySource";

        // Write an informational entry to the event log.    
        myLog.WriteEntry("Writing to event log.");

    }
}
</code>