function Test-MrParameterValidation { [CmdletBinding()] param ( [ValidateNotNullOrEmpty()] [string[]]$ComputerName = $env:COMPUTERNAME ) Write-Output $ComputerName } 详细输出 如果要编写复杂的代码,则内联注释非常有用,但除非用户查看代
[Parameter(Position = 0)] [ValidateNotNullOrEmpty] public string[] Name 重写输入处理方法 如果cmdlet 要处理命令行输入,则必须重写相应的输入处理方法。创建第一个 Cmdlet中引入了基本输入处理方法。 Get-Proccmdlet 重写System.Management.Automation.Cmdlet.ProcessRecord方法来处理用户或脚本提供的Name...
PS>$null-eq$undefinedVariableTrue 如果变量名称键入错误,PowerShell 会将其视为不同的变量,且值为$null。 找到$null值的另一种方法是,当它们来自未提供任何结果的其他命令时。 PowerShell PS>functionGet-Nothing{} PS>$value=Get-NothingPS>$null-eq$valueTrue ...
Check for empty XML element Check for file exists and not zero byte otherwise bypass step execution and log messages Check for files older than 2 minutes and sends out notification if the file still exists check for files that have offline attribute and set it them to archive Check if .txt ...
Checking if a string is NULL or EMPTY is very common requirement in Powershell script. If we don’t do that we will end up with run time errors if we try to perform some operation on that string variable which is empty or null. So the question now is, how to check it?
If there are no matches in the collection, comparison operators return an empty array. For example: PowerShell Copy $a = (1, 2) -eq 3 $a.GetType().Name $a.Count Output Copy Object[] 0 There are a few exceptions: The containment and type operators always return a Boolean ...
Note. Why not? Well, for one thing, it will make your debugging life much easier if your variable names and options correspond. It also makes it quite a bit easier for other people to read – and understand – your script. So what value are we assigning to the variable $yes? Well, ...
A configuration error in the policy results in an empty value for theListeningOnproperty. Use the following command to check the value. PowerShell Get-WSManInstancewinrm/config/listener-Enumerate Output cfg : http://schemas.microsoft.com/wbem/wsman/1/config/listener xsi : http://www....
Handle type inference for redirected commands (#21131) (Thanks @MartinGC94!) Allow empty prefix string in Import-Module -Prefix to override default prefix in manifest (#20409) (Thanks @MartinGC94!) Update variable/property assignment completion so it can fallback to type inference (#21134) ...
And no, for once we’renotkidding; you reallycanuse Windows PowerShell to display messages in the notification area. If you couldn’t, then we’d have had no reason to put together a script like this one: [void] [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") ...