Sstrutt: /* Hashtables */ Added loop

2013-12-17T14:28:51Z

Hashtables: Added loop

← Older revision		Revision as of 14:28, 17 December 2013
Line 86:		Line 86:
	$hash["Name"] = "Value" # Add value to end of array		$hash["Name"] = "Value" # Add value to end of array
	$hash.GetEnumerator() \| Sort-Object -Property Name # Sort hashtable		$hash.GetEnumerator() \| Sort-Object -Property Name # Sort hashtable
			</source>

			To loop through a hash table
			<source lang="powershell">
			$hash.Keys \| % {
			Write-Host "key = $_"
			Write-Host "value = " + $hash.Item($_)
			}
	</source>		</source>

	[[category:PowerShell]]		[[category:PowerShell]]
	[[category:Variables (PowerShell)]]		[[category:Variables (PowerShell)]]

Sstrutt: Initial creation - content from Variables page

2013-06-21T14:39:46Z

Initial creation - content from Variables page

New page

== Creation ==

<source lang="powershell">
$array = @() # Create blank array
$array = @("one", "two", 3) # Create an array with some values
$array += 34 # Add value to end of array
</source>

To create an array (table) with column headings, initialise an array, then create a ''row'' variable with the column headings and add this ''row'' to the array. This is convenient when building a table of data within a loop eg
<source lang="powershell">
$table = @()
foreach ($instance in $set) {
$row = "" | Select Heading1, Heading2, Heading3
$row.Heading1 = "something"
$row.Heading2 = "like"
$row.Heading3 = "this"
$table += $row
}
</source>

== Add rows to an array ==
<source lang="powershell">
> $array = @()
> $row = "" | Select h1,h2,h3
> $row.h1 = "esx1"
> $row.h2 = "HBA1"
> $row.h3 = "LUN1"
> $array = $array + $row
> $row = "" | Select h1,h2,h3
> $row.h1 = "esx2"
> $row.h2 = "HBA1"
> $row.h3 = "LUN2"
> $array = $array + $row
> $array

h1 h2 h3
-- -- --
esx1 HBA1 LUN1
esx2 HBA1 LUN2
</source>

== Select row from array ==
Using above array as example...
<source lang="powershell">
> if (($array |?{$_.h1 -eq "esx2"})) {"true"} else {"false"}
true
> if (($array |?{$_.h1 -eq "esx3"})) {"true"} else {"false"}
false
> $array |?{$_.h1 -eq "esx2"}

h1 h2 h3
-- -- --
esx2 HBA1 LUN2

> $array |?{$_.h1 -eq "esx2"} | Select -ExpandProperty h2
HBA1
</source>

== Array Types ==
.NET Array Lists are far more flexible than PowerShell arrays. With ArrayLists you can easily Add and Remove members and generally enjoy much more flexibility when it comes to manipulating its contents. Despite showing a full range of available methods (when piped through a <code>Get-Member</code>), PS arrays generally don't have many available methods. To confirm the type that you have...

<source lang="powershell">
> $ArrayList.gettype()

IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True ArrayList System.Object

> $PSArray.gettype()

IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
</source>

To force the creation of a .NET array from a PowerShell CmdLet, create one in a fashion such as this...
<source lang="powershell">
$a = New-Object System.Collections.ArrayList # Empty array
$a = New-Object System.Collections.ArrayList(,(Get-Content test.txt)) # Populated with contents of test.txt
</source>

== Hashtables ==
<source lang="powershell">
$hash = @{} # Create blank array
$hash["Name"] = "Value" # Add value to end of array
$hash.GetEnumerator() | Sort-Object -Property Name # Sort hashtable
</source>

[[category:PowerShell]]
[[category:Variables (PowerShell)]]

Arrays (PowerShell) - Revision history

Sstrutt: /* Hashtables */ Added loop

Sstrutt: Initial creation - content from Variables page