将就用着的日志记录类
工作忙，都没什么时间上来发东西，难得五一放假，放一篇先...
日志记录，在项目开发过程中是必不可少的，有了它，在项目投入运作后，当出现了问题，也能有记录作为参考。
.Net 中，日志记录的主要开源项目就是 Log4Net 了，不过它却是过于庞大了，在小系统中，也许只需要记录上错误的信息，所以就有了这个自写的类。
Imports System.IO
Public Class Logger
Private Shared ReadOnly _instance As Logger =New Logger()
Public Shared ReadOnly Property Instance() As Logger
Get
Return _instance
End Get
End Property
Private m_logFolderPath As String
Private Sub New()
Me.m_logFolderPath = Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, "Logs")
If (Not Directory.Exists(Me.m_logFolderPath)) Then
Directory.CreateDirectory(Me.m_logFolderPath)
End If
End Sub
Public Sub [Error](ByVal ex As Exception)
Dim st As New StackTrace()
Dim method As System.Reflection.MethodBase = st.GetFrame(1).GetMethod()
Me.Write(String.Concat(method.DeclaringType.FullName, ".", method.Name), ex.Message)
End Sub
Private Sub Write(ByVal source AsString, ByVal message AsString)
System.Threading.Monitor.Enter(Me)
Globals.ErrorMessage = message
Dim sw As StreamWriter = Nothing
Dim currTime As Date = Date.Now
Dim logFilePath = Path.Combine(Me.m_logFolderPath, String.Concat("ex", currTime.ToString("yyyyMM"), ".log"))
Try
If (File.Exists(logFilePath)) Then
sw = File.AppendText(logFilePath)
Else
sw = File.CreateText(logFilePath)
End If
sw.Write(currTime.ToString("yyyy-MM-dd HH:mm:ss"))
sw.Write("")
sw.Write(source)
sw.Write("")
sw.WriteLine(message)
Finally
If (sw IsNot Nothing) Then
sw.Close()
End If
End Try
System.Threading.Monitor.Exit(Me)
End Sub
End Class
Public Class Logger
Private Shared ReadOnly _instance As Logger =New Logger()
Public Shared ReadOnly Property Instance() As Logger
Get
Return _instance
End Get
End Property
Private m_logFolderPath As String
Private Sub New()
Me.m_logFolderPath = Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, "Logs")
If (Not Directory.Exists(Me.m_logFolderPath)) Then
Directory.CreateDirectory(Me.m_logFolderPath)
End If
End Sub
Public Sub [Error](ByVal ex As Exception)
Dim st As New StackTrace()
Dim method As System.Reflection.MethodBase = st.GetFrame(1).GetMethod()
Me.Write(String.Concat(method.DeclaringType.FullName, ".", method.Name), ex.Message)
End Sub
Private Sub Write(ByVal source AsString, ByVal message AsString)
System.Threading.Monitor.Enter(Me)
Globals.ErrorMessage = message
Dim sw As StreamWriter = Nothing
Dim currTime As Date = Date.Now
Dim logFilePath = Path.Combine(Me.m_logFolderPath, String.Concat("ex", currTime.ToString("yyyyMM"), ".log"))
Try
If (File.Exists(logFilePath)) Then
sw = File.AppendText(logFilePath)
Else
sw = File.CreateText(logFilePath)
End If
sw.Write(currTime.ToString("yyyy-MM-dd HH:mm:ss"))
sw.Write("")
sw.Write(source)
sw.Write("")
sw.WriteLine(message)
Finally
If (sw IsNot Nothing) Then
sw.Close()
End If
End Try
System.Threading.Monitor.Exit(Me)
End Sub
End Class
说明：
1、使用了单例模式，只实例化一次。
2、为了避免写入日志时文件夹不存在，所以我在构造函数里进行判断，这样当调用时，文件夹不存在的话就新建一个，每月一个文件夹。
3、使用反射获取调用的方法，使开发人员可以知道是哪个方法引发异常。
4、针对多线程情况，做了加锁处理。
使用方法：
Public Function Delete(ByVal info As BankInfo) As ExecuteState
Try
Dim intResult As Integer= SqlHelper.ExecuteNonQuery(SqlHelper.ConnectionString, CommandType.Text, SQL_DELETE, Me.GetParameters(info, OperateState.Delete))
If (intResult <=0) Then
Return ExecuteState.Fail
End If
Return ExecuteState.Success
Catch ex As Exception
Logger.Instance.Error(ex)
Return ExecuteState.Error
End Try
End Function
Try
Dim intResult As Integer= SqlHelper.ExecuteNonQuery(SqlHelper.ConnectionString, CommandType.Text, SQL_DELETE, Me.GetParameters(info, OperateState.Delete))
If (intResult <=0) Then
Return ExecuteState.Fail
End If
Return ExecuteState.Success
Catch ex As Exception
Logger.Instance.Error(ex)
Return ExecuteState.Error
End Try
End Function
