我无法使用以下代码下载任何文件:
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
DownloadFile("http://mirror.switch.ch/ftp/mirror/videolan/vlc/2.0.3/vlc-2.0.3.tar.xz", "C:\TEST\vlc-2.0.3.tar.xz")
End Sub
Public Sub DownloadFile(ByVal _URL As String, ByVal _SaveAs As String)
Dim _WebClient As New System.Net.WebClient()
_WebClient.DownloadFile(_URL, _SaveAs)
End Sub
将弹出以下错误:(从德语翻译成英语):
来自Microsoft Error Pop-UP:
==> System.dll中出现了类型为“System.Net.WebException”的未处理的exeption。
在调试器中:
==>执行:触发:“已指定无效参数”(System.Net.Sockets.SocketException)已触发System.Net.Sockets.SocketException。 “已指定无效参数”
完整代码:
Imports System
Imports System.Net
Public Class Form2
Dim str_hd As String
Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
For Each drive As System.IO.DriveInfo In My.Computer.FileSystem.Drives
Dim dbl_capacity As Double
Dim dbl_free As Double
Dim dbl_used As Double
If drive.IsReady Then
dbl_capacity = drive.TotalSize / 1073741824
dbl_free = drive.TotalFreeSpace / 1073741824
dbl_used = dbl_capacity - dbl_free
dbl_capacity = Fix(dbl_capacity * 1) / 1
dbl_free = Fix(dbl_free * 10) / 10
dbl_used = Fix(dbl_used * 10) / 10
str_hd = str_hd & "Laufwerk " & drive.Name & " - " _
& drive.VolumeLabel & vbCrLf _
& "Benutzt: " & dbl_used & " GB" & " / " & dbl_capacity & " GB" & vbCrLf & "Frei: " _
& dbl_free & "GB" & vbCrLf & "-------------------------------" & vbCrLf
End If
Next
txtbox_hd.Text = str_hd
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Form1.Close()
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
DownloadFile("http://www.aerztekammer-hamburg.de/berufsrecht/Berufsordnung.pdf", "C:\TEST\Berufsordnung.pdf")
End Sub
Public Sub DownloadFile(ByVal _URL As String, ByVal _SaveAs As String)
Dim _WebClient As New System.Net.WebClient()
_WebClient.DownloadFile(_URL, _SaveAs)
End Sub
End Class
答案 0 :(得分:1)
文件夹C:\TEST
是否存在?另外,从文档:
在中间层应用程序(如ASP.NET页面)中使用此方法时,如果应用程序执行的帐户无权访问该文件,则会收到错误。
Wenn Sie diese Methode in einer Anwendung der Middle-Tear verwenden,z。 B. einer ASP.NET-Seite,erhalten Sie eine Fehlermeldung,wenn das Konto,unter dem dieAnwendungausgeführtwird,nichtüberdieberechtigung zum Zugriff auf dieDateiverfügt。