PowerShell Hash Tables
Accessing Values
Accessing values in a hash table is straightforward using the key:
# Accessing a value by its key
$name = $person['Name']
Write-Output $name
# Output: John Doe
​
# Using dot notation
$occupation = $person.Occupation
Write-Output $occupation
# Output: Developer
​
​
Removing Entries
Remove entries from a hash table using the Remove method or the Remove-Item
# Remove an entry using Remove method
$person.Remove('City')
# Remove an entry using Remove-Item cmdlet
Remove-Item -Path $person['Occupation']
​
​
Enumerating Hash Table Entries
You can enumerate all key-value pairs in a hash table using a foreach loop:
foreach ($key in $person.Keys) { Write-Output "$key: $($person[$key])" }
​
​
Using Hash Tables to Create Custom Objects
Hash tables can be used to create custom objects, making data manipulation more intuitive:
​
# Create a custom object using a hash table
$customObject = [PSCustomObject]@{ FirstName = "Alice"; LastName = "Johnson"; Department = "IT" }
Write-Output $customObject
​
​
Nested Hash Tables
Hash tables can contain other hash tables as values, allowing for more complex data structures:
​
# Creating a nested hash table
$employee = @{ Name = "Jane Smith"; Contact = @{ Email = "jane.smith@example.com"; Phone = "555-1234" } }
​
# Accessing nested hash table values
$email = $employee.Contact.Email
Write-Output $email
#Output: jane.smith@example.com
​
​
​
#Set Values to Variable
$Hotfix = Get-Hotfix | Select -ExpandProperty HotfixID
$Services = Get-Service | Where {$_.Status -eq "Running"} | Select -ExpandProperty Name
$Enabled_Local_Accounts=Get-WmiObject -Class Win32_UserAccount -Filter {LocalAccount ='True' and Disabled='False'} | Select -ExpandProperty Name
$Drives=Get-PSDrive | Where{$_.Free -ne $Null} | Select -ExpandProperty Name
#Create Hash and Assign Values
$MyHASH=@{
Running_Services=$Services;
Installed_Hotfix=$Hotfix;
Enabled_Local_accounts=$Enabled_Local_Accounts
Hard_Drives=$Drives
}
#Access Hash Data
$MyHASH.Installed_Hotfix
Using Hash Tables in PowerShell: A Guide with Examples:
Hash tables in PowerShell are a powerful way to store and manage data. They consist of key-value pairs, where each key i
s unique, making data retrieval fast and efficient. Here's how you can use hash tables in PowerShell with practical examples:
Creating a Hash Table
To create a hash table, use the @{} syntax:
​
# Create an empty hash table
$hashTable = @{}
​
# Create a hash table with initial key-value pairs
$person = @{
Name = "John Doe"
Age = 30
Occupation = "Developer"
}
​
# Adding a new key-value pair
$person['City'] = 'New York'
​
# Modifying an existing key-value pair
$person['Age'] = 31
Build Datasets \ Assign to Hash
