尝试在用户桌面上创建文件时权限被拒绝

时间:2013-03-02 18:31:43

标签: vb.net file creation

我有一个需要创建日志文件的小型VB应用程序,理想情况下我喜欢用户桌面,因为它很容易看到。

但是,当我尝试创建文件(* .txt文件)时,出现以下错误 -

  

mscorlib.dll中出现'System.UnauthorizedAccessException'类型的第一次机会异常

现在,很明显这是一个权限问题,但我不知道如何解决它,所以我想知道是否有人可以帮助我?感谢。

创建文件的完整代码(取自MSDN,并稍微修改) -

Imports System
Imports System.IO
Imports System.Text

Module write_text

    Public Class Log_File

        '*'
        ' Createa a log file on the users desktop and adds the 'output' text to it
        '
        ' @param required string output The text to output to the log
        '*'
        Public Shared Sub write_to_file(ByVal output As String)

            Dim path As String      ' The path to where the file to create and write should be saved
            Dim file_name As String ' The name of the log file that is to be created

            Debug.Print(vbCrLf & "    write_to_file(){" & vbCrLf)

            ' Set the error handler
            On Error GoTo ExitError

            path = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory)
            file_name = "MusicRenaming - " & Date.Today & ".txt"
            Debug.Print("        Log file: " & path & "\" & file_name)

            ' Check if the file exists
            If File.Exists(path) = False Then

                ' Create a file to write too. 
                Dim sw As StreamWriter = File.CreateText(path)
                sw.WriteLine("Hello")
                sw.WriteLine("And")
                sw.WriteLine("Welcome")
                sw.Flush()
                sw.Close()
                Debug.Print("        File had to be created")

            End If

            ' Open the file to write too
            Dim sr As StreamReader = File.OpenText(path)
            Do While sr.Peek() >= 0
                Console.WriteLine(sr.ReadLine())
                Debug.Print("        Output to file complete")
            Loop

            ' Close the file
            sr.Close()

            Debug.Print(vbCrLf & "    }")

ExitError:
            If Err.Number <> 0 Then functions.error_handler()

        End Sub

    End Class

End Module

请不要 - 我意识到该功能现在不是特别可操作,我只是想先创建文件,然后我会继续处理。

1 个答案:

答案 0 :(得分:0)

感谢@RubensFarias发布in this thread的答案,我能够解决这个问题。

我还在@minitech的建议中将try...catch方法纳入了我的原始问题的评论中,所以希望他对我解决他的问题感到满意:)

Imports System.IO

Module write_text

    Public Class Log_File

        '*'
        ' Createa a log file on the users desktop and adds the 'output' text to it
        '
        ' @param required string output The text to output to the log
        '*'
        Public Shared Sub write_to_file(ByVal output As String)

            Dim file_name As String     ' The name of the log file that is to be created
            Dim file_path As String     ' The full path to where the file to create and write should be saved
            Dim file_exists As Boolean  ' Whether or not the file already exists

            Try

                file_name = "MusicRenaming - " & DateTime.Today.ToString("dd-mm-yyyy") & ".txt"
                file_path = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) & "\" & file_name
                file_exists = File.Exists(file_path)

                Using sw As New StreamWriter(File.Open(file_path, FileMode.OpenOrCreate))
                    sw.WriteLine(output)
                End Using

            Catch oError As Exception
                functions.error_handler(oError)
            End Try

        End Sub

    End Class

End Module