Validate the existence of an AD User with powershell

Validate-ADUser.ps1

# Check if AD User Exist: Method 1
[bool] (Get-ADUser -Filter {SamAccountName -eq "NonExistingADUser" })

# Check if AD User Exist: Method 2
##  supports all valid identity formats
function Test-ADUser {
    [CmdletBinding()]
    param (
        # Identity
        [Parameter(Mandatory=$true)]
        [Alias("User")]
        [string]
        $Identity
    )

    try {
        Get-ADUser -Identity $Identity -ErrorAction Stop | out-null
        return $true
    }
    catch {
        return $false
    }
   
}

Test-ADUser -Identity "NonExistingADUser"