c# 写入文件日志

public static void WriteLog(Model.ModelLog ModelLog)
{
DbAcess dba = new DbAcess();

try
{
//string logFileName =Path.GetFullPath("Log/" + DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString().ToString() + DateTime.Now.Day.ToString() + ".log");
Random random = new Random();
DataTable dt = GetCodeInfo(dba, "37", "0");
string logFolder = ModelLog.RootPath + dt.Rows[0]["CODE_NAME2"].ToString() + "\\" + FormatDateTime(DateTime.Now, Constant.DATETIME_FORMAT_0005) + "\\" + ModelLog.FormName + "\\" + ModelLog.AppCode + "\\";
string logFileName = logFolder + FormatDateTime(DateTime.Now, Constant.DATETIME_FORMAT_0007) + Convert.ToString(random.Next(100000, 999999)) + ".log";

if (!Directory.Exists(logFolder))
{
Directory.CreateDirectory(logFolder);
}

FileInfo fileinfo = new FileInfo(logFileName);

string logTime = DateTime.Now.Year.ToString() + "/" + PadddingLeft(DateTime.Now.Month.ToString(), "0", 2) + "/" + PadddingLeft(DateTime.Now.Day.ToString(), "0", 2) + " " + PadddingLeft(DateTime.Now.Hour.ToString(), "0", 2) + PadddingLeft(DateTime.Now.Minute.ToString(), "0", 2) + PadddingLeft(DateTime.Now.Second.ToString(), "0", 2);
string levelName = "";

switch (ModelLog.LogLevel)
{
case Constant.LogLevel_INFO:
levelName = "INFO";
break;
case Constant.LogLevel_WARNING:
levelName = "WARNING";
break;
case Constant.LogLevel_ERROR:
levelName = "ERROR";
break;
case Constant.LogLevel_CRITICAL:
levelName = "CRITICAL";
break;

}

if (!fileinfo.Exists)
{
//fileinfo.Create();
FileStream fs = fileinfo.OpenWrite();
StreamWriter sw = new StreamWriter(fs);

try
{

sw.BaseStream.Seek(0, SeekOrigin.End);
sw.WriteLine(logTime + " " + ModelLog.LoginId + " " + ModelLog.UserName + " " + levelName + " " + ModelLog.DepartName + " " + ModelLog.LogContent);
sw.Flush();
sw.Close();
}
catch (Exception ex)
{
sw.Flush();
sw.Close();
throw ex;
}
}
else
{
StreamWriter sw = fileinfo.AppendText();

try
{
sw.BaseStream.Seek(0, SeekOrigin.End);
sw.WriteLine(logTime + " " + ModelLog.LoginId + " " + ModelLog.UserName + " " + levelName + " " + ModelLog.DepartName + " " + ModelLog.LogContent);
sw.Flush();
sw.Close();
}
catch (Exception ex)
{
sw.Flush();
sw.Close();
throw ex;
}
}

}
catch (Exception ex)
{

throw ex;
}
finally
{
dba.Dispose();
}
}