Learning how to PowerShell

PowerShellExperiment.ps1

# This PowerShell script was written by Luis Hartmann 2017.
# Use at own risk.
# Intended for educational purposes only.
# Includes code that was borrowed and adjusted from http://www.tomsitpro.com/articles/powershell-interactive-menu,2-961.html

function showMainmenu () {
    param (
        [string]$Title = 'Main Menu'
    )
    #cls
    Write-Host ""
    Write-Host "================ $Title ================"
    Write-Host ""
    Write-Host "1: Addition"
    Write-Host "2: Subtraction"
    Write-Host "3: Color Check"
    Write-Host ""
    Write-Host "0: Exit"
    Write-Host ""

    $input = Read-Host "Please make a selection"
    switch ($input)
    {
        '1' { # Addition
            doAddition
            pressEnter "Press Enter to return to Main Menu"
        }
        '2' { # Subtraction
            doSubstraction
            pressEnter "Press Enter to return to Main Menu"
        }
        '3' { # Color Check
            Write-Host "Let's do a color check!"
            colorCheck
            pressEnter "Press Enter to return to Main Menu"
        }
        '0' { # Exit
            'See you later!'
            exit
        }
    }
}

# pressEnter
# Promts the user to press enter and then returns
# Optional $message can be given
function pressEnter ($message = 'Press Enter to continue'){
    Read-Host $message
    return
}

# doAddition
# Prompts the user for two numbers
# Outputs the sum of the given numbers
function doAddition{
    Write-Host "Let's add up numbers. A + B = C"
    [int]$add_a = Read-Host "Give me number A"
    [int]$add_b = Read-Host "Give me number B"
    [int]$result = $add_a + $add_b
    Write-Host "The result of $add_a + $add_b is" $result
}

# doSubstraction
# Prompts the user for two numbers
# Substracts the second number from the first
# Outputs the result
function doSubstraction{
    Write-Host "Let's subtract numbers. A - B = C"
    [int]$add_a = Read-Host "Give me number A"
    [int]$add_b = Read-Host "Give me number B"
    [int]$result = $add_a - $add_b
    Write-Host "The result of $add_a - $add_b is" $result
}

# colorCheck
# Outputs an awful lot of colorful lines
function colorCheck{
    # Light Colors on Black
    Write-Host "black on black" -foregroundcolor "black" -backgroundcolor "black"
    Write-Host "blue on black" -foregroundcolor "blue" -backgroundcolor "black"
    Write-Host "cyan on black" -foregroundcolor "cyan" -backgroundcolor "black"
    Write-Host "gray on black" -foregroundcolor "gray" -backgroundcolor "black"
    Write-Host "green on black" -foregroundcolor "green" -backgroundcolor "black"
    Write-Host "magenta on black" -foregroundcolor "magenta" -backgroundcolor "black"
    Write-Host "red on black" -foregroundcolor "red" -backgroundcolor "black"
    Write-Host "white on black" -foregroundcolor "white" -backgroundcolor "black"
    Write-Host "yellow on black" -foregroundcolor "yellow" -backgroundcolor "black"
    # Dark Colors on Black
    Write-Host "darkblue on black" -foregroundcolor "darkblue" -backgroundcolor "black"
    Write-Host "darkcyan on black" -foregroundcolor "darkcyan" -backgroundcolor "black"
    Write-Host "darkgray on black" -foregroundcolor "darkgray" -backgroundcolor "black"
    Write-Host "darkgreen on black" -foregroundcolor "darkgreen" -backgroundcolor "black"
    Write-Host "darkmagenta on black" -foregroundcolor "darkmagenta" -backgroundcolor "black"
    Write-Host "darkred on black" -foregroundcolor "darkred" -backgroundcolor "black"
    Write-Host "darkyellow on black" -foregroundcolor "darkyellow" -backgroundcolor "black"
    # Light Colors on White
    Write-Host "black on white" -foregroundcolor "black" -backgroundcolor "white"
    Write-Host "blue on white" -foregroundcolor "blue" -backgroundcolor "white"
    Write-Host "cyan on white" -foregroundcolor "cyan" -backgroundcolor "white"
    Write-Host "gray on white" -foregroundcolor "gray" -backgroundcolor "white"
    Write-Host "green on white" -foregroundcolor "green" -backgroundcolor "white"
    Write-Host "magenta on white" -foregroundcolor "magenta" -backgroundcolor "white"
    Write-Host "red on white" -foregroundcolor "red" -backgroundcolor "white"
    Write-Host "white on white" -foregroundcolor "white" -backgroundcolor "white"
    Write-Host "yellow on white" -foregroundcolor "yellow" -backgroundcolor "white"
    # Dark Colors on White
    Write-Host "darkblue on white" -foregroundcolor "darkblue" -backgroundcolor "white"
    Write-Host "darkcyan on white" -foregroundcolor "darkcyan" -backgroundcolor "white"
    Write-Host "darkgray on white" -foregroundcolor "darkgray" -backgroundcolor "white"
    Write-Host "darkgreen on white" -foregroundcolor "darkgreen" -backgroundcolor "white"
    Write-Host "darkmagenta on white" -foregroundcolor "darkmagenta" -backgroundcolor "white"
    Write-Host "darkred on white" -foregroundcolor "darkred" -backgroundcolor "white"
    Write-Host "darkyellow on white" -foregroundcolor "darkyellow" -backgroundcolor "white"
}


# Entry Point
while($true)
{
    # Go back to main menu no matter what happens
    showMainmenu
}