PowerShell关闭FileStream [英] PowerShell Closing FileStream

问题描述

我正在读取文件，对内容进行加密，然后使用PowerShell将密文写回到文件中.关闭FileStream对象($ inFS)后，它将在pwd(C:\ docs)中创建一个名为"0"的文件.我打开了文件，并在文件中写入了"32".

I am reading in a file, encrypting the contents, and writing the cipher text back out to a file using PowerShell. When the FileStream object ($inFS) is closed, it creates a file in the pwd (C:\docs) named "0". I opened the file and it had "32" written to it.

加密的内容被正确地写入另一个目录中的文件中.我以为缓冲区中还是有东西，所以我尝试了Flush()和Dispose()，但结果相同.为什么会这样?

The encrypted contents are being written to a file in a different directory with no problems. I thought maybe there was something in the buffer still so I tried Flush() and Dispose() but same results. Why is this?

$inFile = 'C:\docs\algorithm_fsa.c'
$inFS = New-Object FileStream($inFile, [FileMode]::Open)

DO
{

  $count = $inFS.Read($data, 0, $blockSizeBytes)
  $offset += $count
  $outStreamEncrypted.Write($data, 0, $count)
  $bytesRead += $blockSizeBytes

}While($count > 0)

$inFS.Close()

推荐答案

在PowerShell中，> 字符用于重定向，以将文本从一个命令传递到文件或另一个流中.

In PowerShell, the > character is used for redirection, to pipe the text from one command into a file, or another stream.

您所在的行

}While($count > 0)

您正在指示PowerShell将 $ count 的内容写入标题为0的文件.无论您碰巧从哪个目录运行脚本，都将执行此操作.

You're instructing PowerShell to write the contents of $count to a file titled 0. It does this, in whichever directory you happened to be running the script from.

将该> 更改为 -GT ，它是PowerShell的大于运算符，您应该得到期望的结果.

Change that > to -GT, which is the PowerShell comparison operator for greater than, and you should get the results you're expecting.

此外，此循环需要更改，因为当前它只会执行一次遍历文件，如 $ count>.0 不是可行的比较.将>替换为 -gt 后，您应该会满意.

Furthermore, this loop needs to be changed because currently, it would only execute one pass through the file, as $count > 0 is not an actionable comparison. Once you replace > with -gt you should be good to go.

这篇关于PowerShell关闭FileStream的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！