VB.NET中使用FTP下载文件的两种方法。

henda

net没有专门处理FTP的类，我们可以通过调用系统自带的FTP.EXE 或者是调用win32 API中的wininet.dll来完成基本操作。希望以下的代码能为大家抛砖引玉。 方法一： 使用Ftp.exe ，通过process类来调用它。Imports System.Diagnostics...Public Sub GetFileByCallFtp()'定义ProcessStartInfo，Process的启动信息。Dim psi As New ProcessStartInfo'ftp.exe的路径最好放到配置文件里。psi.FileName = "C:\WINNT\system32\ftp.exe"psi.RedirectStandardInput = Falsepsi.RedirectStandardOutput = True'该值指示不使用操作系统Shell程序启动进程。psi.UseShellExecute = False'命令集文件名.注意,路径中不能有空格. Dim fileName As String = "C\ftp.txt"    '-s:FileName表示,从文件中读取控制命令psi.Arguments = "-s:" + fileNameDim proc As Processproc = Process.Start(psi)'等待进程完成任务proc.WaitForExit()'在控制台输出结果Console.WriteLine(proc.StandardOutput)Console.ReadLine()End Sub==============================================================================ftp.txt 里的内容方法二，使用win32 api —— wininet.dll首先是，api声明：因为此测试程序，是VB.NET ConsoleApplication所以，api声明写在Module里，方法是静态的。所以没加Shared关键字， 这一点请大家注意。 _Public Function InternetOpen(ByVal sAgent As String, ByVal LAccessType As Integer, ByVal sProxyName As String, _ByVal SProxyBypass As String, ByVal lFlags As Integer) As IntegerEnd Function _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 IntegerEnd Function _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 BooleanEnd Function _Public Function InternetCloseHandle(ByVal hInet As Integer) As IntegerEnd Function调用：Public Sub GetFileByCallWininetDLL()TryDim intinet As Integer = InternetOpen(Nothing, 0, Nothing, Nothing, 0)If intinet > 0 Then'参数：intinet的session值，ftp地址，端口，用户名，密码，lService， lFlags，lContext Dim intinetconn As Integer = InternetConnect(intinet, "192.168.110.152", 0, "tokiwa", "tokiwa", 1, 0, 0)If intinetconn > 0 Then'下载某个文件到指定文件Dim ret As Boolean = FtpGetFile(intinetconn, "pagerror.gif", "C:\itest.gif", 0, 0, 1, 0)If ret ThenConsole.WriteLine("ok!")Console.ReadLine()End IfInternetCloseHandle(intinetconn)InternetCloseHandle(intinet)ElseConsole.WriteLine("can't connect!")Console.ReadLine()End IfElseConsole.WriteLine("ftp wrong!")Console.ReadLine()End IfCatch ex As ExceptionConsole.WriteLine(ex.Message)Console.ReadLine()End TryEnd SubTrackback: http://tb.blog.iyunv.com/TrackBack.aspx?PostId=409766