In order for the TraceSource to write data to the file, you need to set the Switch-property of the TraceSource to a SourceSwitch instance. Change your code as follows:
static void Main(string[] args)
{
TextWriterTraceListener textListener = new TextWriterTraceListener("myListener.log");
// New code starts here
var sourceSwitch = new SourceSwitch("SourceSwitch", "Verbose");
mySource.Switch = sourceSwitch;
// New code ends here
mySource.Listeners.Add(textListener);
// ...
In addition to have the TraceWriter flush its content automatically, set Trace.AutoFlush at the beginning of you main method (the sample works without it, but it is always a good idea to make sure that the listeners are flushed in order not to loose log entries):
static void Main(string[] args)
{
Trace.AutoFlush = true;
// ...
As an alternative, you can also flush the listener explicitly by calling its Flush-method at the end:
textListener.Flush();
mySource.Close();
In real world code, I'd suggest to add a try-finally or using block to assert that Flush is called and that the source is closed.