运行由于特殊字符“|”，批处理文件中的 Powershell 失败

Question

我最近开始使用批处理文件中的一些脚本来完成一些工作，但是当我尝试从 PowerShell 获取一些结果然后对其进行处理时我失败了。

@echo off
setlocal

set "ps= $FindProcess = Get-Process | Where-Object {$_.MainWindowTitle -like 'VNC viewer'};"
set "ps=%ps% $title = $FindProcess.MainWindowTitle ^| Measure-Object -Line;"
set "ps=%ps% $title.Lines"

echo %ps%
for /f "delims=" %%I in ('powershell "%ps%"') do set "title=%%I"
:: For debugging and get the result
:: for /f "delims=" %%I in ('powershell "%ps%"') do echo %%I

echo %title% number of apps have "VNC viewer" title

但是当运行它我抛出 'Where-Object' is not recognized as an internal or external command, operable program or batch file. 并且当把 ^ 放在 | 之前它结果为空 %title% 当取消注释我显示的调试部分时这个错误

 $FindProcess = Get-Process | Where-Object {$_.MainWindowTitle -like 'VNC viewer'}; $title = $FindProcess.MainWindowTitle | Measure-Object -Line; $title.Lines
At line:1 char:124
+ ...  -like 'VNC viewer'}; $title = $FindProcess.MainWindowTitle ^| Measur ...
+                                                                 ~
Unexpected token '^' in expression or statement.
    + CategoryInfo          : ParserError: (:) [], ParentContainsErrorRecordException
    + FullyQualifiedErrorId : UnexpectedToken
ECHO is off.
 number of apps have "VNC viewer" title

Answer 1

我发现删除 echo %ps% 并且不在 | 之前放置 ^ 使其成功运行，但仍然不知道为什么 echo 会抛出错误！

已编辑：阅读评论后，我终于明白为什么了。实际上 echo %ps% 将被解析为 echo what-was-in-the-variable-which-in-this-case-has-|-character 并且如果没有双引号，此命令也将无法工作:)谢谢

运行由于特殊字符“|”，批处理文件中的 Powershell 失败

running Powershell in batch file failed because of special character "|"

powershell

batch-file

cmd

运行 由于特殊字符“|”，批处理文件中的 Powershell 失败

running Powershell in batch file failed because of special character "|"

powershell

batch-file

cmd

运行由于特殊字符“|”，批处理文件中的 Powershell 失败