PowerShell: Ensure a PowerShell Module is available for Script or Function

Get-CheckRequiredModule.ps1

#####
# Require Module as part of a Script
#####
# This examples checks for available PowerCLI module: VMware.VimAutomation.Core
# Add "#REQUIRES" to the top of your .ps1 file
# Use -Modules to specify a Module name
# If the required modules are not in the current session, Windows PowerShell imports them. 
# If the modules cannot be imported, Windows PowerShell throws a terminating error.
# https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_requires?view=powershell-6

# ----- begin
#REQUIRES -Modules VMware.VimAutomation.Core
# ----- end

#####
# Add Module as part of a function:
#####
# This examples checks for available PowerCLI module: VMware.VimAutomation.Core
# If the Module isn't found it attempts to import it. If that fails it writes a warning

# ----- begin
if ((Get-Module VMware.VimAutomation.Core -ErrorAction SilentlyContinue) -eq $null) {
  Import-Module VMware.VimAutomation.Core -ErrorAction Stop -ErrorVariable Error
  If ($Error) {
    Write-Warning -Message "Can't find VMware PowerShell Module!"
  }
}
# ----- end