How To Remove an Item From a PowerShell Array

While most tasks involving arrays in PowerShell are relatively simple, removing an item from an array presents a challenge. PowerShell lacks a native cmdlet specifically for removing items from an array. Even so, there are two methods you can use, both of which I will explain in this article.

Setting Array Items to Null (Easy Method)

The easiest way to remove an item from a PowerShell array is by setting the item's index position to $Null. The approach makes PowerShell treat that position as if it no longer contains a value. Here's how it works:

First, create an array containing the letters A through F. You can do this by entering this command:

$A=@(‘A’, ‘B’, ‘C’, ‘D’, ‘E’, ‘F’)

When you type $A, PowerShell will display the items in the array, as shown in Figure 1.

Array Remove 1

Figure 1. The array $A contains the letters A through F.

Each element in the array corresponds to a numerical index, starting at 0. For example:

Now, suppose you want to remove the letter D. The simple way to do this is by setting the index associated with D to $Null. Use this command:

$A[3]=$Null

When you type $A again, you will see that the letter D is no longer displayed, as shown in Figure 2

Array Remove 2

Figure 2. Setting an array position to $Null removes the value from the array.

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Given the ease with which I removed an array item, you may wonder why I would even bother explaining the hard way of doing this. The reason why is that we haven’t truly removed the item from the array. Although this method removes the value, it retains the original structure. It continues to have six positions, even though one is empty. For example, typing $A.count will still return 6. Additionally:

Array Remove 3

Figure 3. The array position has not been deleted.

In some cases, this method works perfectly fine. However, having empty array positions can cause problems in some situations. If that is the case, you will need a different approach, which is a bit more complicated than what we have so far covered.

Manual Array Reconstruction (Hard Method)

According to Microsoft documentation, adding an item to a PowerShell array involves setting up a brand-new array. Thankfully, PowerShell handles this process automatically. However, removing an item from an array requires you to construct a new array manually. PowerShell doesn’t handle this for you.

Here is how you can fully remove an item from an array:

$A=@('A','B','C','D','E','F')

$A

$Index=0

$TotalItems=$A.count

ForEach ($Item in $A){            

	If ($Item -eq 'D') {

		$Position=$Index

	}            

	$Index=$Index+1            

}

Write-Host 'the position is ' $Position

# Copy the letters before D

$B=@($Null)

For ($Counter=0; $Counter -lt $Position; $Counter++) {            

	$B+=$A[$Counter]            

}

#Copy the letters after D

For ($Counter=$Position+1; $Counter -le $TotalItems; $Counter++) {            

	$B+=$A[$Counter]            

}

$A = $B

$A

This script does the same thing we did a moment ago: It extracts the letter D.

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Unlike the first method, which sets the target position to $Null but keeps the array structure intact, this method reconstructs the array entirely. As a result: