PowerShell:条件“if”语句的异常行为

这是预期的行为。我认为你可能误解了控制流程的进展。

$CACHE_OS = ""
$OPERATINGSYSTEM = "WIN832_9200"

if ( $OPERATINGSYSTEM -match "WIN832" )  # true
{
  $CACHE_OS = "WIN832"  # $cache_os set to "WIN832"
}
else
{
  $CACHE_OS = $OPERATINGSYSTEM
}

# at this point $cache_os has a value of "WIN832"

if ( $OPERATINGSYSTEM -match "WIN864" ) # false
{
  $CACHE_OS = "WIN864"
}
else # control goes here
{
  $CACHE_OS = $OPERATINGSYSTEM   # $cache_os is re-assigned, new value is "WIN832_9200"
}

$CACHE_OS  # output the current value ("WIN832_9200")

也许你的意思是用 elseif 陈述

$CACHE_OS = ""
$OPERATINGSYSTEM = "WIN832_9200"

if ( $OPERATINGSYSTEM -match "WIN832" )
{
  $CACHE_OS = "WIN832"
}
elseif ( $OPERATINGSYSTEM -match "WIN864")
{
  $CACHE_OS = "WIN864"
}
else
{
  $CACHE_OS = $OPERATINGSYSTEM
}

它正在按预期工作。在第一个IF中,$OPERATINGSYSTEM匹配“WIN832”,因此$CACHE_OS被设置为“WIN832”,正如您所期望的, ELSE语句列表不执行 。

在第二个IF中,$OPERATINGSYSTEM与“WIN832”不匹配,因此跳过IF语句列表 ELSE部分开始 中,并且$CACHE_OS被分配了$OPERATINGSYSTEM的值,即“WIN832_9200”。