Microsoft Technologies Articles - Page 185 of 204

$Errorview variable determines the display format of the error message in PowerShell. Before PowerShell 7 there were mainly two views, Normal View (Default view)Category ViewWith PowerShell version 7, one new additional error view category is included and now there are 3 $ErrorView categories for version 7.Concise View (Default)Normal ViewCategory ViewWe will understand each view one by one.A ) Normal ViewIt is the default view before PowerShell version 7 and it produces the detailed multiline errors and bit noisy. It includes the exception name, category, line number of the error, etc.$ErrorView = 'NormalView' Get-ChildItem C:\NoDirectoryOutputGet-ChildItem : Cannot find path 'C:\NoDirectory' because ... Read More

PowerShell version 7 has introduced a few new null operators. They are as below.Null-Coalescing operator - ??Null Conditional Assignment Operators - ??=Null Conditional member access operators - ?. and ?[]a. Null-Coalescing operator - ??Null Coalescing operator ??evaluates the left-hand side condition or operand and if it is null then evaluates the right-hand side operand otherwise provides the value of the left-hand side operand.For example, Without the Null-Coalescing operator, we would have written a script like as shown below, $Name = $null if($Name -eq $null){"Name is Null"} Else {"PowerShell"}The above same condition can be written with the ?? operator.$name = $null ... Read More

The validateCount attribute in PowerShell function is to validate the length of an array, which means that you can pass the specific number of arguments into the parameter. In the below example we need array should contain a minimum 1 and maximum 4 values when we pass the values. For that, we will write the below script, Function ValidateArray {    Param (       [ValidateCount(1, 3)]       [String[]]$Animals    )    return $PSBoundParameters }OutputPS C:\> ValidateArray -Animals Cow, Dog, Cat Key Value --- ----- Animals {Cow, Dog, Cat}The above output is valid but when we pass ... Read More

The ValidateScript attribute is to validate the script before entering inside the function. For example, let say you want to validate the path of the file, validate the remote computer connectivity, etc. We will take here remote server connectivity example.Without the ValidateScript attribute, we would have written the script as shown below.Function Check-RemoteServer {    param (       [string]$Server    )    if(Test-Connection -ComputerName $Server -Count 2 -Quiet -ErrorAction Ignore) {       Write-Output "$server is reachable"    } else {       Write-Output "$Server is unreachable"    } }OutputPS C:\> Check-RemoteServer -Server asde.asde asde.asde is ... Read More

The ValidateLength attribute in PowerShell is used to validate the length of the String. Generally how we write the command without the mentioned attribute is using the Length method and if/else condition for the string. For Example, Function ValidateStorageName {    param (       [String]$StorageName    )    if(($StorageName.Length -gt 3) -and ($StorageName.Length -lt 15)) {       Write-Output "`nStorage Name validated"    } else {       Write-Output "`nStorage Name validation failed"    } }Output−PS C:\> ValidateStorageName -StorageName Alpha Storage Name validated PS C:\> ValidateStorageName -StorageName CN Storage Name validation failedWith the ValidateLength attribute, else ... Read More

The ValidateSet attribute in PowerShell function is to validate the values entered from the set which means, it allows only specific values from the set. To understand better consider the below example, we have an array and we need to check if entered values are among array or not then we will use the below code.Function PetAnimalsCheck {    param(       [String]$Animal    )    $Animals = "Cow", "Dog", "Cat", "Horse", "Camel", "Elephant"    if($Animals -contains $Animal) {       Write-Output "Animal is in the list of Pet Animals"    } else {       Write-Output ... Read More

Validation parameters are a set of rules that you define on the PowerShell variable and restrict users from entering some values and binding users to enter values in the specific domain. If there are not validation parameters the script would be lengthy. The ValidateRange attribute is one of them.ValidateRange AttributeThis parameter is to validate the specific range of numbers. For example, If we need users to enter a value between 5 and 100 and we simply write the script using the If/else statement as shown below.function AgeValidation {    param(       [int]$age    )    if(($age -lt 5) ... Read More

To search for the word in PowerShell and replace it in the file we will use the string operation. In fact, the Get-Content command in PowerShell is used to read almost any type of file content. In this article, we are considering one text file as shown below.Get-Content C:\Temp\TestFile.txtOutputPS C:\> Get-Content C:\Temp\TestFile.txt # In case of linux, networkInterface names are of the form eth* # In Windows, please use the network full name from Device Manager networkInterfaces: ["Microsoft Hyper-V Network Adapter" ] overrideMetricsUsingScriptFile: false scriptTimeoutInSec: 60 scriptFiles: - osType: windows filePath: monitors/NetworkMonitor/scripts/windows-metrics.bat - osType: unixBase filePath: monitors/NetworkMonitor/scripts/unix-base-metrics.shThe ... Read More

As we know $ErrorActionPreference and $ErrorAction both have the same functionality and both are used to handle terminating errors by converting Non-Terminating errors to Terminating errors. But when both the variables are used, we need to know which takes precedence.$ErrorActionPreference variable is used at the start of the script while the $erroraction variable is a common parameter and used with the cmdlet. In some cases, we might need the script to be terminated as soon as an error occurs but inside the script, we have some cmdlets which need to be ignored or continued if the error occurs. In that ... Read More

Scriptblock is a set of commands which can be executed together when they are invoked. In PowerShell, generally, we write individual commands. Scriptblock can be written with two curly brackets.Example$sb = {Get-Process powershell; Get-Service W32Time}Here we have written two commands under scriptblock. If you directly run this command, scriptblock treats them as a string.PS C:\> $sb Get-Process powershell; Get-Service W32TimeTo run the commands inside the scritblock, use Invoke-Command with the -Scriptblock parameter.Invoke-Command -ScriptBlock $sbOutputHandles NPM(K)    PM(K)    WS(K)    CPU(s)    Id    SI    ProcessName ------- ------    -----    -----    ------    --    --   ... Read More