小弟刚学vb.net,请帮忙解释下下面代码，明白了马上给分
#Region "タリテストにヘッダ送 "

Private Sub TransHeadBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TransHeadBtn.Click

Dim l_strLog, l_strKind As String

Try
If LogList.SelectedIndex = -1 Then Exit Try

'ログの取得
l_strLog = CStr(LogList.Items(LogList.SelectedIndex))
l_strKind = l_strLog.Substring(24, 2)

'ＳＥＣＮＥＴ文でない合、了
If l_strKind <> "S " AndAlso _
l_strKind <> "R " AndAlso _
l_strKind <> "D " AndAlso _
l_strKind <> "T " Then Exit Try

l_strLog = l_strLog.Remove(0, 26)

g_cTestTool.SetTarryHeader(l_strLog.Substring(0, 29))

Catch Err As Exception
'エラログ
LogWrite(EN_LOGKIND.EN_ERROR, "File :fmLog.vb Method :ClipBoardBtn_Click() Message : " & Err.Message)
End Try
End Sub

#End Region

其中LogList为我的ListBox名字，希望能详细讲解下这段代码是什么功能以及其中部分代码的具体意思，谢谢

[解决办法]
#Region "タリテストにヘッダ送 "

Private Sub TransHeadBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TransHeadBtn.Click

Dim l_strLog, l_strKind As String

Try
If LogList.SelectedIndex = -1 Then Exit Try

'ログの取得-取得LOG
l_strLog = CStr(LogList.Items(LogList.SelectedIndex)) ' 读取选中的Item值
l_strKind = l_strLog.Substring(24, 2)

'ＳＥＣＮＥＴ文でない合、了-读到不是电文处结束
If l_strKind <> "S " AndAlso _
l_strKind <> "R " AndAlso _
l_strKind <> "D " AndAlso _

l_strKind <> "T " Then Exit Try ' 当Item值的第24、25两位不是 "S "或 "R "或 "D "或 "T "时，退出

l_strLog = l_strLog.Remove(0, 26) ' 删除值的前26位

g_cTestTool.SetTarryHeader(l_strLog.Substring(0, 29)) ' 把值的前29位设为保留头

Catch Err As Exception
'エラログ-error log
LogWrite(EN_LOGKIND.EN_ERROR, "File :fmLog.vb Method :ClipBoardBtn_Click() Message : " & Err.Message)
End Try
End Sub

#End Region