how to merge multiple scripts and use functions to show output - powershell

Question

A couple of you (Shay especially!) helped me yesterday and I have managed to come up with multiple scripts and am now merging them into one.
The problem is that I have put them all into "Functions" and one function relies on the successful check on a hotfix - if the hotfix is not installed then the script has to stop right there and then - that is the first check the script does. How do I get the next function to call the successful output of the hotfix function?
Also I have no idea how to call the functions - ie at the bottom I put the name of the functions one line after each other but ended up looping over and over!
hope someone can assist.
Write-Host "=================================="
Write-Host "Pre-Staging Script for DFSR Server"
Write-Host "=================================="
Function Service
{
Write-Host "=================================="
Write-Host "Checking Service Installation"
Write-Host "=================================="
write-host "This will check if Hotfix KB979808 is installed." -ForegroundColor Black -BackgroundColor Cyan
write-host "This is required for Windows Server 2008 R2 Robocopying" -ForegroundColor Black -BackgroundColor Cyan
Write-Host ""
$hotfix1 = Get-HotFix -id KB979808 -ErrorAction SilentlyContinue
If($hotfix1)
{
Write-Host "Hotfix is installed you may proceed" -foregroundcolor "green"
Write-Host ""
}
else
{
Write-Host "Hotfix is NOT installed - Please ensure you install this hotfix BEFORE" -ForegroundColor "red"
Write-host "Copying any data" -foregroundcolor "red"
Write-Host ""
}
}
Function Robocopy ($hotfix1)
{
Write-Host "============="
Write-Host "Robocopy Data"
Write-Host "============="
$Source = Read-Host "Please enter path of SOURCE"
$Destination = Read-Host "Please enter path of TARGET"
$Output = Read-Host "Please enter where to place output file eg c:\temp\COPY.log"
robocopy $Source $Target /b /e /copyall /r:1 /xd dfsrprivate /log:$Output /tee
}
Function Comparision
{
Write-Host "==============================================="
Write-Host "Checking Directory Count and Folder comparision" -ErrorAction SilentlyContinue -BackgroundColor Cyan -ForegroundColor Black
Write-Host "==============================================="
Write-Host ""
$Source = Read-Host "Please enter Source directory to check"
$Target = Read-Host "Please enter Target directory to check"
Write-Host ""
If($source -and (Test-Path -Path $source -PathType Container))
{
"There are $(#(Get-ChildItem $Source).Count) items in the '$Source' directory"
}
Else
{
Write-Host "Please enter a directory"
}
If($source -and (Test-Path -Path $Target -PathType Container))
{
"There are $(#(Get-ChildItem $Target).Count) items in the '$Target' directory"
}
Else
{
Write-Host "Please enter a directory"
}
Write-Host ""
$child1 = Get-ChildItem -Path $Source -Recurse -Force
$child2 = Get-ChildItem -Path $Target -Recurse -Force
Compare-Object $child1 -DifferenceObject $child2 -Property Name
Write-Host ""
Write-Host "NOTE:" -BackgroundColor Cyan -ForegroundColor Black
Write-Host "Any symbols with '=>' mean that the file Does NOT exist in SOURCE but is in the Target" -BackgroundColor Cyan -ForegroundColor Black
Write-Host "Any symbols with '<=' mean that the file Does NOT exist in TARGET but is in the Source" -BackgroundColor Cyan -ForegroundColor Black
}

Answer 1

To use the hotfix found in the function Service, you should return the hotfix to a variable. The function would look like this:
Function Service
{
Write-Host "=================================="
Write-Host "Checking Service Installation"
Write-Host "=================================="
write-host "This will check if Hotfix KB979808 is installed." -ForegroundColor Black -BackgroundColor Cyan
write-host "This is required for Windows Server 2008 R2 Robocopying" -ForegroundColor Black -BackgroundColor Cyan
Write-Host ""
# This will return any output.
Get-HotFix -id KB979808 -ErrorAction SilentlyContinue
}
Then the function calls would be:
$hotfix = Service
if($hotfix) {
Robocopy
}
else {
# This will exit the script.
return
}
Function Robocopy doesn't need $hotfix1 as a parameter since it's not used anywhere in the function.
The Robocopy function is probably looping because the call to robocopy.exe is the same as your Robocopy function; try adding ".exe" to the robocopy.exe call. It is important to name functions to accurately reflect their purpose. Service could be Get-HotFixKB979808 and Robocopy could be Start-MyRobocopy
Having said all that, since your functions do very specific things, they really don't need to be their own functions. You could change them to be more reusable by having them accept parameters.