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Now that we have an array, how do we access items from it?

Indexing

The easiest way to access an item from an array is to use its index number. An index is the position number of an item. Consider the example below:

$colors = "red", "yellow", "black", "blue"
#.          0       1         2       3

The numbers underneath the items represent their indices. An array’s indices always start at 0. If we want to access black, for example, we must offset – or skip – 2 times.

PS > $colors[2]
black

As shown above, the syntax for accessing an array item in PowerShell involves brackets [ ]. If we provide an index that is out of bounds, such as 10, PowerShell will not create an error but instead return $null. The $null value would result in no output if printed to the terminal but has other behaviors depending on the situation.

Each array object has a Length property that gives us the number of items in that array. The property Count will return the same value.

Updating Items

We can also update items by utilizing indices. To change the color yellow to brown, for example:

PS > $colors[1] = "brown"
PS > $colors
red
brown
black
blue

Special Index Tricks

PowerShell offers much more flexibility when indexing items such as

Multiple indices: separate indices with commas to print multiple items:
```
PS > $colors[0,2]
red
black
```
The example above displays the values at index 0 and 2.
Range operator ..: print all items between two indices:
```
PS > $colors[1..3]
brown
black
blue
```
The above example displays the values from index 1 to index 3.
Reverse range: use range operator from a higher index to a lower index to print items in reverse order (inclusive)
```
PS > $colors[2..1]
black
brown
```
The above example displays the values from index 2 to index 1.
Negative indices: items are referenced in reverse order where the last item has index -1
```
PS > $colors[-1]
blue
```
The above example displays the value in the last index, 3.

Iteration

Each array object has a method called ForEach that allows us to perform the same action on each array item. We can use the variable PSItem or underscore _ to refer to each item in the array.

PS > $colors.ForEach({ $PSItem.Length })
3
5
5
4

The example above is printing the length of each string of our colors array. red has a length of 3, brown is 5, and so on.

Instructions

In the open PowerShell script, assign the variable favorite to pho using indexing.

Click Run to continue.

Change curry to samosa in the food array using indexing.

Click Run to move on to the next checkpoint.

Create a variable named fast_food and assign the items pizza, burrito, and fries from the food array.

Use the multiple indices trick.

Click Run to move on.

Create a variable named reverse_food that holds the food array in reverse order.

Use the reverse range trick.

Click Run when you are done.

Use iteration on the fast_food array. Inside the curly braces, write the following:

"Fast foods: " + $PSItem

Click Run when you are done.

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