PowerShell Scripting - The Basics  

Kari said:

PowerShell has no issues with logical operators. In screenshot beginning of a sample script reading 3 numbers and outputting them in ascending order, comparison in IF statement uses one AND operator (-and in PS) and in ELSEIF statement two AND operators:
Attachment 159748

You can use AND (-and), OR (-or), XOR (-xor) and NOT (-not).




Yes it is.

Code:

if (this condition is met)
     {
     Do this
     Then do this
     Finally do this, too
     }

An IF statement can also include other IF statements:

Code:

if (this condition is met)
     {
     if (this condition is met, too)
          {
          Do this
          Then do this
          Finally do this, too
          }
     Do this
     Do that
     }

Kari

Thanks very much. I shall have to experiment now .

slicendice said:

@cereberus

I am sorry, I must have used only half my brain this morning and read your question only partially. I did not answer your question at all. Instead I got stuck at your comment about the funny looking operators.

The correct answer to your question is exactly what @Kari said.

No problem - we all have brain fart days.

HippsieGypsie said:

Is there a way to get v6?

PowerShell Core, still in beta, is a relatively new version of PowerShell, difference to original native Windows PowerShell being it's open source and can be installed and used in Windows, Linux and Mac. PowerShell Core is currently in version 6.0.0-beta.8: Releases · PowerShell/PowerShell · GitHub

Although (almost fully) compatible with Windows native PS, I recommend staying in native PS until the time comes that both versions merge to one. Current version of native Windows PS is 5.1:

HippsieGypsie said:

I have a PS ISE tile on my Start screen. Is there a way to start the program with Admin rights without going through the UAC prompt? I have to right click the tile and go through its context menu to start in that mode. First-world problem I know.

Create an elevated shortcut for it: Create Elevated Shortcut without UAC prompt in Windows 10 Customization Tutorials

Kari

cereberus said:

Thanks very much. I shall have to experiment now .

Just remember to use parentheses and curly brackets correctly.
IF (this) {DO that}
IF ((this) -or (this)) {DO that}
IF ((this) -and (this)) {DO that}

A "real life" example of using OR (-or), from second tut in PS scripting (will be published in couple of hours) about using a PS script to create bootable USB Windows 10 install media, I'll use a conditional statement as shown below in CODE box to check if the folder / mounted ISO given by user contains Windows setup files by checking if install.wim or install.esd exists either in \Sources folder (single bit architecture ISO) or at least in one of either \x86\Sources and x64\Sources folders (dual architecture ISO).

Script has read user input just before storing it, either drive letter for a mounted W10 ISO or path to a folder containing files copied from ISO, in variable $ISOFolder. Using cmdlet Test-Path to check if a file exists, if true the condition is met:

Code:

$WimCount = 0
if ((Test-Path $ISOFolder\Sources\install.wim) -or 
    (Test-Path $ISOFolder\x86\Sources\install.wim) -or
    (Test-Path $ISOFolder\x64\Sources\install.wim) -or
    (Test-Path $ISOFolder\Sources\install.esd) -or 
    (Test-Path $ISOFolder\x86\Sources\install.esd) -or
    (Test-Path $ISOFolder\x64\Sources\install.esd))
        {$WimCount = 1}        
    else 
        {
        cls
        Write-Host
        Write-Host ' No Windows 10 installation files found.'
        Write-Host ' Please check mounted ISO letter or path'
        Write-Host ' to folder containing installation files'
        Write-Host ' and run script again.'
        Write-Host
        Pause
        Exit
        }

Using five OR operators to check if any of six conditions is met is not very elegant but it does the job :)

Kari

When the scripting basics is clear, see the next part in PS scripting tutorials: PowerShell Scripting - Create USB Install Media for Windows 10 Installation Upgrade Tutorials

DrEmpiricism said:

The proper way to do any If statements is by using Try/Catch/Finally blocks.

Hahahah! Are you serious?

Kari said:

Just remember to use parentheses and curly brackets correctly.
IF (this) {DO that}
IF ((this) -or (this)) {DO that}
IF ((this) -and (this)) {DO that}

A "real life" example of using OR (-or), from second tut in PS scripting (will be published in couple of hours) about using a PS script to create bootable USB Windows 10 install media, I'll use a conditional statement as shown below in CODE box to check if the folder / mounted ISO given by user contains Windows setup files by checking if install.wim or install.esd exists either in \Sources folder (single bit architecture ISO) or at least in one of either \x86\Sources and x64\Sources folders (dual architecture ISO).

Script has read user input just before storing it, either drive letter for a mounted W10 ISO or path to a folder containing files copied from ISO, in variable $ISOFolder. Using cmdlet Test-Path to check if a file exists, if true the condition is met:

Code:

$WimCount = 0
if ((Test-Path $ISOFolder\Sources\install.wim) -or 
    (Test-Path $ISOFolder\x86\Sources\install.wim) -or
    (Test-Path $ISOFolder\x64\Sources\install.wim) -or
    (Test-Path $ISOFolder\Sources\install.esd) -or 
    (Test-Path $ISOFolder\x86\Sources\install.esd) -or
    (Test-Path $ISOFolder\x64\Sources\install.esd))
        {$WimCount = 1}        
    else 
        {
        cls
        Write-Host
        Write-Host ' No Windows 10 installation files found.'
        Write-Host ' Please check mounted ISO letter or path'
        Write-Host ' to folder containing installation files'
        Write-Host ' and run script again.'
        Write-Host
        Pause
        Exit
        }

Using five OR operators to check if any of six conditions is met is not very elegant but it does the job :)

Kari

Actually, I think it is very elegant and clear.

DrEmpiricism said:

The proper way to do any If statements is by using Try/Catch/Finally blocks.

This is the first part of series of PowerShell scripting tutorials I intend to write in coming months, emphasis in words first part. The idea of this tutorial is to introduce concept of PS scripting to those not familiar with it. Error handling, "catch" in coding principle try - catch - finally you refer to does most certainly not belong to it.

In similar way this tutorial tells nothing about do while loops or functions or calling VBS from PS script or many other features and finesses of PS scripting. Your comment is like asking why math textbook for grade 5 does not mention Riemannian geometry.

cereberus said:

Actually, I think it is very elegant and clear.

That conditional statement is now "live" in the next part of PS scripting tuts: PowerShell Scripting - Create USB Install Media for Windows 10 Installation Upgrade Tutorials

Kari