vb.net 对于文件的的简单操作

''' <summary>
''' パラメータの読み書き
''' </summary>
''' <returns>成功か？失敗か？</returns>
''' <remarks></remarks>
Public Function SaveOrReadParameters(ByVal writeOaread As String) As Boolean
SaveOrReadParameters = False
Dim temp As StreamWriter
'目録を創建する
If (Not Directory.Exists(FILEPATH)) Then
Directory.CreateDirectory(FILEPATH)
End If
'ファイルを書く
If writeOaread = "write" Then
'ファイル判断存在か？
Dim Boo_DirExist As Boolean = System.IO.File.Exists(filepath & fileName)
If Boo_DirExist Then
'ファイル存在
File.Delete(FILEPATH & FILENAME)
temp = File.CreateText(FILEPATH & FILENAME)
Else
'ファイルが無し
temp = File.CreateText(FILEPATH & FILENAME)
End If
Try
Using sw As StreamWriter = temp
sw.WriteLine(txtSyohin_kana.Text & ";")
sw.WriteLine(txtSyohin.Text & ";")
sw.WriteLine(txtBunnrui.Text & ";")
sw.WriteLine(txtNomekuti.Text & ";")
sw.WriteLine(txtMennkaa.Text & ";")
sw.WriteLine(txtYouki.Text & ";")
sw.WriteLine(txtYouryoumin.Text & ";")
sw.WriteLine(txtYouryoumax.Text & ";")
sw.WriteLine(txtTannkamin.Text & ";")
sw.WriteLine(txtTannkamax.Text)
sw.Flush()
sw.Close()
End Using
Catch ex As Exception
Application.ExitThread()
Finally

End Try
'ファイルを読む
ElseIf writeOaread = "read" Then
Dim line As String = String.Empty
Dim Boo_DirExist As Boolean = System.IO.File.Exists(FILEPATH & FILENAME)
If Boo_DirExist = False Then
'ファイルが無し
Return False
End If
Using sr As StreamReader = New StreamReader(FILEPATH & FILENAME)
Do While sr.Peek() > 0
line = line & sr.ReadLine()
Loop
sr.Close()
End Using
If line <> "" Then
txtSyohin_kana.Text = line.Split(";")(0)
txtSyohin.Text = line.Split(";")(1)
txtBunnrui.Text = line.Split(";")(2)
txtNomekuti.Text = line.Split(";")(3)
txtMennkaa.Text = line.Split(";")(4)
txtYouki.Text = line.Split(";")(5)
txtYouryoumin.Text = line.Split(";")(6)
txtYouryoumax.Text = line.Split(";")(7)
txtTannkamin.Text = line.Split(";")(8)
txtTannkamax.Text = line.Split(";")(9)
Else
Return False
End If
End If
Return True
End Function