PowerShell 複製 if ( $array.count -gt 0 ) { "Array isn't empty" } 還有一個陷阱可以注意這裡。 即使您有單一物件,也可以使用 count ,除非該物件是 PSCustomObject。 這是 PowerShell 6.1 中修正的錯誤。這是好消息,但很多人仍然在5.1,需要注意它。PowerShell 複製 ...
PS> $empty = $null PS> $empty[0] Error: Cannot index into a null array. 因此,在尝试访问数组中的元素之前,请确保数组不是 $null。Count数组和其他集合具有计数属性,可告知数组中有多少项。PowerShell 复制 PS> $data.count 4 PowerShell 3.0 向大多数对象添加了计数属性。 你可以使用单个对象,它应该...
Count - This property is the most commonly used property to determine the number of items in any collection, not just an array. It's an [Int32] type value. In Windows PowerShell 5.1 (and older) Count alias property for Length. Length - This property is an [Int32] type value. This ...
首选项变量:首选项变量存储 PowerShell 的用户首选项。 这些变量由 PowerShell 创建,并使用默认值填充。 用户可以更改这些变量的值。 例如,该$MaximumHistoryCount变量会确定会话历史记录中的最大条目数。 有关详细信息、列表和首选项变量的说明,请参阅about_Preference_Variables。
Incidentally, you can determine the number of items in an array simply by echoing back the value of theCountproperty, like so: $a.Count Oh, one more thing: what if you to get rid ofallthe items in the array? Here’s one thought; call theClearmethod: ...
Sort-Object uses the Property parameter to sort the objects by Count. The Descending parameter displays the output by count, from highest to lowest. In the output, the Count column contains the total number of each event. The Name column contains the grouped event Id n...
You can also use this technique In the context of a conditional statement, such as theifstatement. PowerShell if($textFiles=Get-ChildItem*.txt) {$textFiles.Count } In this example, if no files match, theGet-ChildItemcommand returns nothing and assigns nothing to$textFiles, which is consider...
You bet we do: because this is an array, we can use theCountproperty to determine the number of items in the array. And, if you look closely at the code, you’ll see that this is exactly what we do with Where-Object: {$_.GetFiles().Count -eq 0} ...
A set of PowerShell functions you might use to enhance your own functions and scripts or to facilitate working in the console. Most should work in both Windows PowerShell and PowerShell 7, even cross-platform. Any operating system limitations should be h
To access the errors returned by these jobs, you instead access the errors in its first child job (called child job number zero). See Also Improve the Performance of Large-Scale WMI Operations Invoke a Command on a Remote Computer Notify Yourself of Job Completion Problem You want to notify...