/// <summary>
/// Returns the specified number of log entries of the specified category, starting with the latest one.
/// </summary>
/// <param name="category">The category of the log entries to be returned (-1 for "all").</param>
/// <param name="maxItems">The maximum number of items returned (-1 for "all").</param>
/// <param name="logfilePath">For environments where "AppDomain.CurrentDomain.BaseDirectory" doesn't work reliably, the path to the nLog.csv file can be explicitly specified here.</param>
/// <returns>A list of LogEntrys or null.</returns>
public static List <ErrorLogEntry> GetLogEntries(LogEntryCategories category, int maxItems, DateTime startTime, DateTime endTime, string searchText, string myLogfilePath = null)
{
Exception ex;
myLogfilePath = myLogfilePath ?? logFilePath;
DataTable dtEntries = CsvHandler.ReadCSVFile(myLogfilePath, out ex);
if (dtEntries == null || ex != null)
{
LastException = ex;
return(null);
}
bool displayAllCategories = (int)category == -1 ? true : false; //determine if all entries have to be displayed
List <ErrorLogEntry> entriesToReturn = new List <ErrorLogEntry>();
for (int i = dtEntries.Rows.Count - 1; i >= 0; i--) //iterate the table from bottom to top (new to old)
{
DateTime entryTime;
string categoryString = category.ToString();
if (displayAllCategories || dtEntries.Rows[i].ItemArray[2].ToString() == categoryString) //category matches the input parameter
{
if (!DateTime.TryParse(dtEntries.Rows[i].ItemArray[0].ToString(), out entryTime))
{
entryTime = endTime;
}
if (entryTime >= startTime && entryTime <= endTime)
{
if (string.IsNullOrEmpty(searchText) || (dtEntries.Rows[i].ItemArray[3].ToString().Contains(searchText) || dtEntries.Rows[i].ItemArray[4].ToString().Contains(searchText)))
{
ErrorLogEntry newLogEntry = new ErrorLogEntry()
{
Time = entryTime, LogLevel = dtEntries.Rows[i].ItemArray[1].ToString(), Category = dtEntries.Rows[i].ItemArray[2].ToString(), Message = dtEntries.Rows[i].ItemArray[3].ToString(), ExceptionText = dtEntries.Rows[i].ItemArray[4].ToString(), CodeLine = dtEntries.Rows[i].ItemArray[5].ToString()
};
entriesToReturn.Add(newLogEntry);
}
}
}
if (maxItems > 0 && entriesToReturn.Count == maxItems)
{
break;
}
}
return(entriesToReturn);
}
/// <summary>
/// Saves a new log entry.
/// </summary>
/// <param name="category">The category of the entry.</param>
/// <param name="message">The text to be displayed.</param>
/// <param name="exception">An optional Exception object.</param>
public static void AddLogEntry(LogEntryCategories category, string message, Exception exception = null, string className = "", [CallerMemberName] string memberName = "", [CallerLineNumber] int sourceLineNumber = 0)
{
if (!WriteLogFile)
{
return;
}
#region LogLevel check
if (LogLevel == LogLevels.None)
{
return;
}
if (category == LogEntryCategories.Debug || category == LogEntryCategories.Info || category == LogEntryCategories.Other)
{
if (LogLevel == LogLevels.ErrorsOnly)
{
return;
}
}
#endregion
if (message != null)
{
message = message.Replace(';', ',').Replace(Environment.NewLine, " |-> ").Replace("\"", "'"); //make sure that the message does not contain any line breaks (the current CSV reader does not support multiple multi-line columns)
}
message = (string.IsNullOrEmpty(className) ? null : className + ".") + memberName + "[" + sourceLineNumber + "]: " + message;
if (exception != null && exception.Message != null)
{
exception = new Exception(exception.ToString().Replace(';', ',').Replace("\"", "'")); //prevent semicolons and apostrophe in exception messages because the exceptions are written to a CSV file
}
LogLevel logLevel = NLog.LogLevel.Info;
switch (category)
{
case LogEntryCategories.Debug:
logLevel = NLog.LogLevel.Debug;
break;
case LogEntryCategories.Error:
logLevel = NLog.LogLevel.Error;
break;
case LogEntryCategories.Fatal:
logLevel = NLog.LogLevel.Fatal;
break;
case LogEntryCategories.Info:
logLevel = NLog.LogLevel.Info;
break;
case LogEntryCategories.Trace:
logLevel = NLog.LogLevel.Trace;
break;
case LogEntryCategories.Warning:
logLevel = NLog.LogLevel.Warn;
break;
default:
logLevel = NLog.LogLevel.Error;
break;
}
LogEventInfo newLogEntry = new LogEventInfo(logLevel, "", message);
newLogEntry.Properties["category"] = category.ToString(); //custom field 'category'
newLogEntry.Properties["codeLine"] = sourceLineNumber; //custom field 'codeLine'
newLogEntry.Exception = exception;
applicationLogger.Log(newLogEntry);
if (category == LogEntryCategories.Error || category == LogEntryCategories.Fatal) //only store errors
{
lock (errorListLock)
{
if (LatestErrors == null)
{
LatestErrors = new List <LogEntry>();
}
while (LatestErrors.Count > 1000)
{
LatestErrors.RemoveAt(0);
}
LatestErrors.Add(new ErrorLogEntry()
{
Category = category.ToString(), ExceptionText = exception?.ToString(), Message = message, Time = DateTime.Now, LogLevel = logLevel.ToString()
});
}
}
//log event
OnLogEvent?.Invoke(null, new ErrorLogEntry()
{
Category = category.ToString(), ExceptionText = exception.ToString(), Message = message, LogLevel = logLevel.ToString(), Time = DateTime.Now, CodeLine = sourceLineNumber.ToString()
});
}
