.net - PowerShell:System.Net.WebClient.DownloadFile不会下载从ListDirectory收集的文件

Question

我正在尝试从FTP服务器下载一些zip文件。 FTP服务器的结构如下

ftp://ftp.example.com
|
 -> /Download
    | 
     -> file1.zip, file2.zip, file3.zip etc

我已将所有文件拉入名为 $ftpFiles的数组中

foreach ($zip in $ftpFiles)
{
    $LocalFile = "C:\Temp\$zip"
    $RemoteFile = "$site/$zip"
    $ftp = New-Object System.Net.WebClient
    $ftp.Credentials = new-object System.Net.NetworkCredential($Username, $realPassword)
    $uri = New-Object System.Uri("$RemoteFile")
    $ftp.DownloadFile($uri, $LocalFile)
    Write-Host "$zip download complete"
}

问题是 $ftp.DownloadFile无法与我的 $LocalFile变量一起使用。但是，如果我手动输入 $LocalFile信息，它将成功。

例如

$ftp.DownloadFile($uri, "C:\temp\file1.zip")

效果很好，但是

$ftp.DownloadFile($uri, $LocalFile)

给我以下错误

Exception calling "DownloadFile" with "2" argument(s): "An exception occurred during a WebClient request."
At line:1 char:34
 +                 $ftp.DownloadFile <<<< ($uri, $LocalFile)
 + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
 + FullyQualifiedErrorId : DotNetMethodException

出于调试目的，我一直在做

write-host $LocalFile

它将正确返回为

C:\Temp\file1.zip

如我所料。

我只能假定 DownloadFile不喜欢嵌套变量，并且将其读取为 C:\Temp\$zip，但不确定如何解决它。

编辑:评论想看看 $files数组是如何建立的

$site = $ftpbase + $dir

$ftp = [System.Net.FtpWebRequest]::Create("$site")
$ftp.Method = [System.Net.WebRequestMethods+FTP]::ListDirectory #Details
$ftp.Credentials = new-object System.Net.NetworkCredential($Username, $realPassword)

$response = $ftp.getresponse() 
$stream = $response.getresponsestream() 

$buffer = new-object System.Byte[] 1024 
$encoding = new-object System.Text.AsciiEncoding 

$outputBuffer = "" 
$foundMore = $false 

## Read all the data available from the stream, writing it to the 
## output buffer when done. 
do 
{

    ## Allow data to buffer for a bit 
    start-sleep -Seconds 2 

    ## Read what data is available 
    $foundmore = $false 
    $stream.ReadTimeout = 1000

    do 
    { 
        try 
        { 
            $read = $stream.Read($buffer, 0, 1024) 

            if($read -gt 0) 
            { 
                $foundmore = $true 
                $outputBuffer += ($encoding.GetString($buffer, 0, $read))

            } 
        } catch { $foundMore = $false; $read = 0 } 
    } while($read -gt 0) 
} 
while($foundmore)

$files = $outputBuffer -split ("\n")

Answer 1

ListDirectory的输出为ASCII模式，其中行由\r\n分隔。您仅按\n分割输出，因此\r保留在文件名中。

由于文件file1.zip\r不存在，因此下载失败。

打印file1.zip\r时，看不到\r。