If you are new to PowerShell, this document will walk you through a few examples to give you some basic ideas of PowerShell. We recommend that you open a PowerShell console/session and type along with the instructions in this document to get most out of this exercise.
As mentioned above PowerShell commands is designed to have Verb-Noun structure, for instance Get-Process, Set-Location, Clear-Host, etc. Let’s exercise some of the basic PowerShell commands also known as **cmdlets**.
**1. Get-Process**: displays the processes running on your system.
By default, you will get data back similar to the following:
``` PowerShell
PS C:\>Get-Process
Handles NPM(K) PM(K) WS(K) VM(M) CPU(s) Id ProcessName
**2. Clear-Host**: Clears the display in the command window
```PowerShell
PS C:\> Get-Process
PS C:\> Clear-Host
```
Type too much just for clearing the screen? Here is how the alias can help.
**3. Get-Alias**: Improves the user experience by using the Cmdlet aliases
To find the available aliases, you can type below cmdlet:
```PowerShell
PS C:\> Get-Alias
CommandType Name
----------- ----
…
Alias cat -> Get-Content
Alias cd -> Set-Location
Alias cls -> Clear-Host
Alias cp -> Copy-Item
Alias clv -> Clear-Variable
Alias gmo -> Get-Module
Alias man -> help
Alias rm -> Remove-Item
Alias ls -> Get-ChildItem
Alias type -> Get-Content
…
As you can see "cls" is an alias of Clear-Host. Now try it:
PS C:\> Get-Process
PS C:\> cls
```
**4. cd - Set-Location**: change your current working directory
```PowerShell
PS C:\> Set-Location C:\test
PS C:\test>
```
**5. ls or dir - Get-ChildItem**: list all items in the specified location
```PowerShell
Get all files under the current directory:
PS C:\test> Get-ChildItem
Get all files under the current directory as well as its subdirectories:
PS C:\test> dir -Recurse
List all files with file extension "txt".
PS C:\test> ls –Path *.txt -Recurse -Force
```
**6. New-Item**: Create a file
```PowerShell
An empty file is created if you type the following:
PS C:\test> New-Item -Path c:\test\test.txt
Directory: C:\test
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 7/7/2016 7:17 PM 0 test.txt
```
You can use the **-value** parameter to add some data to your file. For example, the following command adds the phrase "Hello World" as a file content to the test.txt. Because the test.txt file exists already, we use **-force** parameter to replace the existing content.
There are other ways to add some data to a file, for example, you can use Set-Content to set the file contents:
```PowerShell
PS C:\test>Set-Content -Path c:\test\test.txt -Value "Hello World too!"
```
Or simply use ">>" as below:
```
# create an empty file
"" > empty.txt
# set "hello world!!!" as content of text.txt file
"hello world!!!" > test.txt
```
The pound sign (#) above is used for comments in PowerShell.
**7. type, cat - Get-Content**: get the content of an item
```PowerShell
PS C:\>Get-Content -Path "C:\Test\test.txt"
PS C:\>type -Path "C:\Test\test.txt"
Hello World!
```
**8. rm, del - Remove-Item**: delete a file or folder
This cmdlet will delete the file c:\test\test.txt:
```PowerShell
PS C:\test> Remove-Item c:\test\test.txt
```
**9. Exit**: - to exit the PowerShell session, type "exit"
```PowerShell
PS C:\test> exit
```
Need Help?
----
The most important command in PowerShell is possibly the Get-Help, which allows you to quickly learn PowerShell without having to surfing around the Internet. The Get-Help cmdlet also shows you how PowerShell commands work with examples.
PS C:\>**Get-Help**
You can use this cmdlet to get help with any PowerShell commands.
PS C:\>**Get-Help -Name Get-Process**
It shows the syntax and other technical information of the Get-Process cmdlet.
PS C:\>**Get-Help -Name Get-Process -Examples**
It displays the examples how to use the Get-Process cmdlet.
If you use **-full** parameter, i.e., "Get-Help -Name Get-Process -Full", it will display more technical information.
Discover All Commands Available on Your System
----
You want to discover what PowerShell cmdlets available on your system. Simple, just run "Get-Command" as below.
PS C:\> **Get-Command**
If you want to know whether a particular cmdlet exists on your system, you can do something like below:
PS C:\> **Get-Command Get-Process**
If you want to know the syntax of Get-Process cmdlet, type
PS C:\> **Get-Command Get-Process -Syntax**
If you want to know how to sue the get-process, type
PS C:\> **Get-Help Get-Process -example**
PowerShell Pipeline '|'
----
Sometimes when you run Get-ChildItem or "dir", you want to get a list of files in a descending order. To archive that, type:
```PowerShell
PS C:\> dir | sort -Descending
```
Say you want to get the largest file in a directory
- You can use ISE, VS Code, or any favorite editor to create a PowerShell script and save the script with a .ps1 file extension (helloworld.ps1 in the example)
- To run the script, cd to your current folder and type .\helloworld.ps1
See [Running PowerShell Scripts Is as Easy as 1-2-3] [run-ps] for more details.
