.net沒有專門處理FTP的類，我們可以通過呼叫系統自帶的FTP.EXE 或者是呼叫win32 API中的wininet.dll來完成基本操作。希望以下的程式碼能為大家拋磚引玉。

方法一： 使用Ftp.exe ，通過process類來呼叫它。

Imports System.Diagnostics

...

  Public Sub GetFileByCallFtp()

       '定義ProcessStartInfo，Process的啟動資訊。

        Dim psi As New ProcessStartInfo

        'ftp.exe的路徑最好放到配置檔案裡。

        psi.FileName = "C:/WINNT/system32/ftp.exe"

        psi.RedirectStandardInput = False

        psi.RedirectStandardOutput = True

        '該值指示不使用作業系統Shell程式啟動程序。

        psi.UseShellExecute = False

        '命令集檔名.注意,路徑中不能有空格.

        Dim fileName As String = "C/ftp.txt"    

        '-s:FileName表示,從檔案中讀取控制命令

        psi.Arguments = "-s:" + fileName

        Dim proc As Process

        proc = Process.Start(psi)

        '等待程序完成任務

        proc.WaitForExit()

        '在控制檯輸出結果

        Console.WriteLine(proc.StandardOutput)

        Console.ReadLine()

    End Sub

==============================================================================

ftp.txt 裡的內容

方法二，使用win32 api —— wininet.dll

首先是，api宣告：

   因為此測試程式，是VB.NET ConsoleApplication所以，api宣告寫在Module裡，

   方法是靜態的。所以沒加Shared關鍵字， 這一點請大家注意。

    <DllImport("wininet")> _
    Public Function InternetOpen(ByVal sAgent As String, ByVal LAccessType As Integer, ByVal sProxyName As String, _
                                  ByVal SProxyBypass As String, ByVal lFlags As Integer) As Integer
    End Function

    <DllImport("wininet")> _
    Public Function InternetConnect(ByVal hInternetSession As Integer, ByVal sServerName As String, _
                                    ByVal nServerPort As Integer, ByVal sUsername As String, _
                                    ByVal sPassword As String, ByVal lService As Integer, _
                                    ByVal lFlags As Integer, ByVal lContext As Integer) As Integer
    End Function

    <DllImport("wininet")> _
    Public Function FtpGetFile(ByVal hFtpSession As Integer, ByVal lpszRemoteFile As String, _
                               ByVal lpszNewFile As String, ByVal fFailIfExists As Boolean, _
                               ByVal dwFlagsAndAttributes As Integer, ByVal dwFlags As Integer, _
                               ByVal dwContext As Integer) As Boolean
    End Function

    <DllImport("wininet")> _
    Public Function InternetCloseHandle(ByVal hInet As Integer) As Integer
    End Function

    呼叫：

     Public Sub GetFileByCallWininetDLL()
        Try
            Dim intinet As Integer = InternetOpen(Nothing, 0, Nothing, Nothing, 0)
            If intinet > 0 Then

                '引數：intinet的session值，ftp地址，埠，使用者名稱，密碼，lService， lFlags，lContext

                Dim intinetconn As Integer = InternetConnect(intinet, "192.168.110.152", 0, "tokiwa", "tokiwa", 1, 0, 0)

                If intinetconn > 0 Then

                    '下載某個檔案到指定檔案

                    Dim ret As Boolean = FtpGetFile(intinetconn, "pagerror.gif", "C:/itest.gif", 0, 0, 1, 0)

                    If ret Then
                        Console.WriteLine("ok!")
                        Console.ReadLine()
                    End If
                    InternetCloseHandle(intinetconn)
                    InternetCloseHandle(intinet)
                Else
                    Console.WriteLine("can't connect!")
                    Console.ReadLine()
                End If

            Else
                Console.WriteLine("ftp wrong!")
                Console.ReadLine()
            End If
        Catch ex As Exception
            Console.WriteLine(ex.Message)
            Console.ReadLine()
        End Try

    End Sub