/// <summary>
/// Writes lines to the log file.
/// </summary>
/// <returns>The task.</returns>
private static async Task WriteLogFileAsync()
{
// get the Logs folder
Folder = ApplicationData.Current.LocalFolder;
Folder = await Folder.CreateFolderAsync(FOLDER_NAME, CreationCollisionOption.OpenIfExists);
// get the two log files
File2 = await Folder.CreateFileAsync("2.log", CreationCollisionOption.OpenIfExists);
File1 = await Folder.CreateFileAsync("1.log", CreationCollisionOption.OpenIfExists);
// get the current log file
BasicProperties prop1 = await File1.GetBasicPropertiesAsync();
BasicProperties prop2 = await File2.GetBasicPropertiesAsync();
CurrentFile = (prop1.DateModified >= prop2.DateModified) ? File1 : File2;
var stream = await CurrentFile.OpenStreamForWriteAsync();
stream.Seek(0, SeekOrigin.End);
// process log file events
List <string> myMessages = new List <string>();
while (true)
{
// wait for an event
signal.WaitOne();
// clear the log files
if (clear)
{
CurrentFile = File1 = await Folder.CreateFileAsync("1.log", CreationCollisionOption.ReplaceExisting);
File2 = await Folder.CreateFileAsync("2.log", CreationCollisionOption.ReplaceExisting);
clear = false;
Cleared.Invoke(null, EventArgs.Empty);
}
// get the messages to be written
lock (messages)
{
myMessages.AddRange(messages);
messages.Clear();
}
// write the messages to the current log file
foreach (string message in myMessages)
{
Debug.WriteLine(message);
try
{
byte[] bytes = Encoding.UTF8.GetBytes(message);
await stream.WriteAsync(bytes);
stream.WriteByte(13);
await stream.FlushAsync();
}
catch (Exception ex)
{
Debug.WriteLine("AppendTextAsync EXCEPTION: " + ex.Message);
}
}
myMessages.Clear();
// switch log files if necessary
BasicProperties prop = await CurrentFile.GetBasicPropertiesAsync();
if (prop.Size >= maxFileSize)
{
if (CurrentFile == File1)
{
CurrentFile = File2 = await Folder.CreateFileAsync("2.log", CreationCollisionOption.ReplaceExisting);
}
else
{
CurrentFile = File1 = await Folder.CreateFileAsync("1.log", CreationCollisionOption.ReplaceExisting);
}
stream = await CurrentFile.OpenStreamForWriteAsync();
stream.Seek(0, SeekOrigin.End);
}
}
}