在命令内使用变量 (PowerShell)
$computer = gc env:computername
# Argument /RU '$computer'\admin isn't working.
SchTasks /create /SC Daily /tn "Image Verification" /ST 18:00:00 /TR C:\bdr\ImageVerification\ImageVerification.exe /RU '$computer'\admin /RP password
基本上我需要在计划任务中提供计算机名称...
提前谢谢您！
$computer = gc env:computername
# Argument /RU '$computer'\admin isn't working.
SchTasks /create /SC Daily /tn "Image Verification" /ST 18:00:00 /TR C:\bdr\ImageVerification\ImageVerification.exe /RU '$computer'\admin /RP password
Basically I need to provide the computer name in the scheduled task...
Thank you in advance!
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（2）
单引号字符串不会在 PowerShell 中扩展变量。尝试使用双引号字符串，例如：
Single quoted strings will not expand variables in PowerShell. Try a double quoted string e.g.:
要补充 Keith Hill 的有用答案，请提供其他信息：
两者
"$computer\admin"和不带引号的形式，$computer\admin，可以工作，因为不带引号的字符串参数隐式被视为就像它们是"..."-封闭（双-引号），即可扩展字符串执行字符串插值（用它们的值替换嵌入的变量引用和表达式），而不是逐字字符串 ('...'< /强>, 单引号），不解释其内容。如有疑问，请显式使用
"..."，特别是当字符串包含|和<等元字符时code>有关如何将不带引号的标记解析为命令参数的完整规则，请参阅此答案 。
陷阱：
您尝试的部分引用：
即使更正为
"$computer"\admin以使插值工作，也不会 工作，因为 PowerShell - 也许令人惊讶 - 然后将$computer的值和逐字字符串\admin作为两个传递 论点。 只有当部分引用的复合字符串以不带引号的字符串开头时，它才会被识别为单个参数（例如$computer"\ admin”可以） - 请参阅此答案了解更多信息。另一个值得注意的陷阱是只有独立变量引用，例如
$computer和$env:COMPUTERNAME可以按原样嵌入在“...”中；要嵌入表达式（包括属性访问和索引访问）或命令，您需要 >将它们括在$(...)中，即 子表达式运算符。例如，要将表达式$someArray[0]或$someObj.someProp的值嵌入可扩展字符串中，必须使用"$($someArray[0 ])"或"$($someObj.someProp)"- 参见 此答案了解完整规则。To complement Keith Hill's helpful answer with additional information:
Both
"$computer\admin"and the unquoted form,$computer\admin, would work, because unquoted string arguments are implicitly treated as if they were"..."-enclosed (double-quoted), i.e. as expandable strings that perform string interpolation (replace embedded variable references and expressions with their values), as opposed to verbatim strings ('...', single-quoted) that do not interpret their content.When in doubt, use
"..."explicitly, notably when the string contains metacharacters such as|and<For the complete rules on how unquoted tokens are parsed as command arguments, see this answer.
Pitfalls:
The partial quoting you attempted:
even if corrected to
"$computer"\adminto make interpolation work, would not work, because PowerShell - perhaps surprisingly - then passes the value of$computerand verbatim string\adminas two arguments. Only if a compound string with partial quoting starts with an unquoted string is it recognized as a single argument (e.g.$computer"\admin"would work) - see this answer for more information.Another notable pitfall is that only stand-alone variable references such as
$computerand$env:COMPUTERNAMEcan be embedded as-is in"..."; to embed an expression - which includes property access and indexed access - or a command, you need to enclose them in$(...), the subexpression operator. E.g., to embed the value of expression$someArray[0]or$someObj.somePropin an expandable string, you must use"$($someArray[0])"or"$($someObj.someProp)"- see this answer for the complete rules.