Webclient.DownloadFile 至 Folderbrowser.Selectedpath

Question

我希望我的代码从网站下载文件并将其保存到用户在 FolderBrowserDialog 中选择的目录中......我已经尝试了下面的代码但没有成功： ' Download the files If My.Computer.Network.IsAvailable Then Try wClient.DownloadFile(New Uri("DOWNLOAD LINK"), FolderBrowserDialog1.SelectedPath & "FILENAME.123") wClient.DownloadFile(New Uri("DOWNLOAD LINK"), FolderBrowserDialog1.SelectedPath & "FileName.123) wClient.DownloadFile(New Uri("Download LINK"), FolderBrowserDialog1.SelectedPath & "FileName.123") Catch ex As Exception MessageBox.Show(ex.Message) End Try

Answer 1

这是我为您编写的一些示例代码，可以帮助您入门。首先我们将 wClient 声明为带有 Events 的 WebClient 这样我们就可以触发文件下载时发生的事情。

我使用 VLC 媒体播放器作为示例下载，更改以满足您的需要。注意我用一个你不需要做的按钮点击事件来做到这一点。

Imports System.ComponentModel
Imports System.Net
Public Class Form1
Private WithEvents wClient As New WebClient()
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    Dim FolderBrowserDiaglog1 As New FolderBrowserDialog()
    Dim folderPath As String = ""
    Dim fileName As String = "vlc.exe"

    Dim downloadFile As String = "https://get.videolan.org/vlc/2.2.6/win32/vlc-2.2.6-win32.exe" ''VLC MEDIA PLAYER
    If FolderBrowserDiaglog1.ShowDialog() = DialogResult.OK Then
        folderPath = FolderBrowserDiaglog1.SelectedPath
    End If
    If My.Computer.Network.IsAvailable Then
        Dim combinePath As String = System.IO.Path.Combine(folderPath, fileName)
        wClient.DownloadFileAsync(New Uri(downloadFile), combinePath)
    End If
End Sub

Private Sub wClient_DownloadFileCompleted(sender As Object, e As AsyncCompletedEventArgs) Handles wClient.DownloadFileCompleted
    MessageBox.Show("File Downloaded")
End Sub
End Class

查看 wClient 的事件列表并查看许多可用的选项，例如我制作的在文件下载后显示消息框的选项.

Web 客户端事件 https://msdn.microsoft.com/en-us/library/system.net.webclient_events(v=vs.110).aspx

Webclient.DownloadFile 至 Folderbrowser.Selectedpath

Webclient.DownloadFile to Folderbrowser.Selectedpath

vb.net

dialog

webclient