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? Well, belo...
Here,ifblock checks if variable has a truthy value, so it will go toelseifblock even if value is0,$false, an empty String, anempty array, and not just$null, and that’s the reason, we have put explicit check inelseifstatement if variable is$null. ...
The variable is not null. Let’s assign an empty string value to a variable and check again. If a variable is not assigned, it also has a null value. $string=""if($string) {Write-Host"The variable is not null."}else{Write-Host"The variable is null." ...
if($value-is[string] ) {# do something} 如果您正在使用類別或接受管線上的各種物件,您可以使用這個方法。 您可以將服務或服務名稱作為輸入。 然後檢查您是否有服務,並在只有名稱時擷取服務。 PowerShell if($Service-isnot[System.ServiceProcess.ServiceController] ) {$Service=Get-Service-Name$Service} ...
functionTest-MrParameterValidation{ [CmdletBinding()]param( [Parameter(Mandatory)] [string[]]$ComputerName)Write-Output$ComputerName} 如果尚未指定,可能需要为ComputerName参数指定默认值。 问题是,默认值不能与必需参数一起使用。 请改用具有默认值的ValidateNotNullOrEmpty参数验证属性。
functionTrapTest {trap{"Error found:$_"} nonsenseString } TrapTest 运行此版本的函数将返回以下输出: Output Error found: The term 'nonsenseString' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was inclu...
<UnixDomainSocketEndPoint>] [-Proxy <Uri>] [-ProxyCredential <PSCredential>] [-ProxyUseDefaultCredentials] [-Body <Object>] [-Form <IDictionary>] [-ContentType <String>] [-TransferEncoding <String>] [-InFile <String>] [-OutFile <String>] [-PassThru] [-Resume] [-SkipHttpErrorCheck] [...
<UnixDomainSocketEndPoint>] [-Proxy <Uri>] [-ProxyCredential <PSCredential>] [-ProxyUseDefaultCredentials] [-Body <Object>] [-Form <IDictionary>] [-ContentType <String>] [-TransferEncoding <String>] [-InFile <String>] [-OutFile <String>] [-PassThru] [-Resume] [-SkipHttpErrorCheck] [...
<UnixDomainSocketEndPoint>] [-Proxy <Uri>] [-ProxyCredential <PSCredential>] [-ProxyUseDefaultCredentials] [-Body <Object>] [-Form <IDictionary>] [-ContentType <String>] [-TransferEncoding <String>] [-InFile <String>] [-OutFile <String>] [-PassThru] [-Resume] [-SkipHttpErrorCheck] [...
check if object is $null Check if OS is 32bit or 64bit check If Process Is Running in another computer Check if SMB1 is enabled on the AD servers Check if string contains invalid characters Check if string starts with letter/character. check installed memory with physical memory Check networ...