当你分析文本日志或筛选不通类型的信息时，你通常要使用 Where-Object。这里有一个通用脚本来说明复合筛选：
# logical AND filter for ALL keywords
Get-Content -Path C:\windows\WindowsUpdate.log |
Where-Object { $_ -like '*successfully installed*' } |
Where-Object { $_ -like '*framework*' } |
Out-GridView
# above example can also be written in one line
# by using the -and operator
# the resulting code is NOT faster, though, just harder to read
Get-Content -Path C:\windows\WindowsUpdate.log |
Where-Object { ($_ -like '*successfully installed*') -and ($_ -like '*framework*') } |
Out-GridView
# logical -or (either condition is met) can only be applied in one line
Get-Content -Path C:\windows\WindowsUpdate.log |
Where-Object { ($_ -like '*successfully installed*') -or ($_ -like '*framework*') } |
Out-GridView
