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...
It returnsTrueif the string is empty andFalseif it is not empty. [string]::IsNullOrEmpty($new) Output: True Now, let’s assign a string value to a variable. $new="asdf"[string]::IsNullOrEmpty($new) Output: False You can also use theIsNullOrWhiteSpacemethod to check if a string variable...
[string]::IsNullOrEmpty($newVariable) OUTPUT 1 2 3 False This time, we got False because the $newVariable is not null or empty but contains a string type value, Hello World. 6.2 Using IsNullOrWhiteSpace() Method we can use the IsNullOrWhiteSpace() method to check if the specified str...
[-ComputerName <System.String[]>] [-Credential <System.Management.Automation.PSCredential>] [<CommonParameters>] DESCRIPTION > This cmdlet is only available on the Windows platform. The `Get-HotFix` cmdlet uses the Win32_QuickFixEngineering WMI class to list hotfixes that are installed on the ...
如果需要参数有多个值,指定类型为string[] functionTest-MrParameterValidation { [CmdletBinding()]param( [Parameter(Mandatory)] [string[]]$ComputerName) Write-Output$ComputerName} 如果需要指定一个默认参数需要将ValidateNotNullOrEmpty参数验证属性与默认值一起使用,不过不能与必需(Mandatory)参数一起使用!
functionTest-MrParameterValidation{ [CmdletBinding()]param( [Parameter(Mandatory)] [string[]]$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参数验证属性。
Please note that while checking if array contains any element, it also check for its datatype. Mixed data types 1 2 3 4 5 $myArray=42,"PowerShell",$true,19.99 $item="42" $result=$myArray.Contains($item) Here, $result will be $false because "42" (string) is not the same type ...
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 network drive connection Chec...
Revert "Allow empty prefix string in 'Import-Module -Prefix' to overr… Apr 28, 2025 test Revert "Allow empty prefix string in 'Import-Module -Prefix' to overr… Apr 28, 2025 tools Update metadata.json (#25438) Apr 29, 2025
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...