除上述方法外,还可以在PowerShell中使用IsNullOrEmpty静态方法。 使用-eq运算符检查字符串是否为null或empty -eq运算符用于比较两个值是否相等。您可以将字符串与一个空字符串进行比较,以检查它是否为空。 代码: $str1=""if($str1-eq"") {Write-Host"String is empty"}else{Write-
function Test-MrParameterValidation { [CmdletBinding()] param ( [Parameter(Mandatory)] [string[]]$ComputerName ) Write-Output $ComputerName } 如果没有指定 ComputerName 参数,也许要为其指定一个默认值。问题是,默认值不能与强制性参数一起使用。 取而代之的是使用带有默认值的 ValidateNotNullOrEmpty ...
如需變更的完整清單,請參閱 GitHub 存放庫中的CHANGELOG。 如需 .NET 9 的詳細資訊,請參閱 [.NET 9 的新功能][07]。 重大變更 修正Test-Path在使用PathType和日期範圍時的-OlderThan和-NewerThan參數(#20942)(感謝 @ArmaanMcleod!)) 先前,如果-OlderThan一起指定,這個元素會被忽略。
[string]$ComputerNmae) Write-Output$ComputerNmae} 如果需要参数有多个值,指定类型为string[] functionTest-MrParameterValidation { [CmdletBinding()]param( [Parameter(Mandatory)] [string[]]$ComputerName) Write-Output$ComputerName} 如果需要指定一个默认参数需要将ValidateNotNullOrEmpty参数验证属性与默认值一起...
<string[]> -like <wildcard-expression> <string[]> -notlike <wildcard-expression> <string[]> -match <regular-expression> <string[]> -notmatch <regular-expression> When the input of these operators is a scalar value, they return a Boolean value. When the input is a collection of value...
If you typeGet-SmallFileswithout a value, the function assigns 100 to$size. If you provide a value, the function uses that value. Optionally, you can provide a brief help string that describes the default value of your parameter, by adding thePSDefaultValueattribute to the description of your...
In fact, this week we’re going to do something very similar. One seeming-advantage of a graphical-oriented application is that it’s easy to constrain a user to a finite set of choices: if you display a message box that contains onlyYesandNobuttons, well, at that point it’s difficult...
Select-String Select-Xml Send-MailMessage Set-Alias Set-Date Set-MarkdownOption Set-PSBreakpoint Set-TraceSource Set-Variable Show-Command Show-Markdown Sort-Object Start-Sleep Tee-Object Test-Json Trace-Command Unblock-File Unregister-Event ...
Stringify ErrorRecord with empty exception message to empty string (#24949) (Thanks @MatejKafka!) Add completion single/double quote support for -PSEdition parameter for Get-Module (#24971) (Thanks @ArmaanMcleod!) Error when New-Item -Force is passed an invalid directory name (#24936) (Than...
If this parameter is empty, all messages are returned. Note: The Search-Mailbox cmdlet returns up to 10000 results per mailbox if a search query is specified. Expand table Type: String Position: Named Default value: None Required: False Accept pipeline input: False Accept wildcard characters...