Often you may want to check if an input value provided by a user in PowerShell exists in a particular array.
You can use the following syntax to do so:
$user_input -in $my_array
This particular example checks if the user input value stored in the variable named $user_input exists in the array named $my_array.
This statement will either return True or False.
You can also use the -notin operator to check if the user input value does not exist in an array:
$user_input -notin $my_array
The following example shows how to use this syntax in practice.
Example: How to Check if Input Value Exists in Array in PowerShell
Suppose we create an array named $good_teams that contains the names of various basketball teams and then we use the Read-Host cmdlet to prompt the user to enter a team name.
We can use the -in operator to check if the value provided by the user exists in the array:
$good_teams = @('Mavs', 'Lakers', 'Spurs', 'Nets')
$user_input = Read-Host 'Enter team name'
$user_input -in $good_teams
The following screenshot shows how to use this syntax in practice:
In this particular example we typed in Lakers for the user input.
Since this team name exists in the array named $good_teams, the -in operator returns True.
Suppose instead that we typed in Celtics for the user input:
Since this team name does not exist in the array named $good_teams, the -in operator returns False.
Note: You can find the complete documentation for the -in, -notin and other comparison operators in PowerShell here.
Related Tutorials
The following tutorials explain how to perform other common tasks in PowerShell:
PowerShell: How to Replace Multiple Strings in File
PowerShell: How to Replace Special Characters in String
PowerShell: How to Replace Text in String
