Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Explain variable / Array scope in PowerShell function.
Generally, when the variable is declared as a Public variable or outside the function in the script (not in any other variable or condition), you don’t need to pass that value to function because the function retains the value of the variable when the variable is initialized before the function is called.
Example
function PrintOut{
Write-Output "your Name is : $name"
}
$name = Read-Host "Enter your Name"
PrintOutIn the above example, $name variable is declared outside the function called PrintOut. So as the variable can be read inside the function, you can directly use the variable by its name.
Output
Enter your Name: PowerShell your Name is : PowerShell
On the contrary, when you have the $name variable declared inside and when you check the output outside the function, you won’t get the value of the variable.
Example
function PrintOut{
$name = Read-Host "Enter your Name"
}
PrintOut
Write-Output "your Name is : $name"Output
Enter your Name: PowerShell your Name is :
You can see in the above output the value of the $Name is NULL as $name is declared inside the function.
On the other hand, if the variable or array is declared outside the function and when you modify the value of the variable or array inside the function, it doesn’t reflect outside of the function.
Example
function PrintOut{
$name = Read-Host "Enter your Name"
Write-Output "Name inside function : $name"
}
$name = "Alpha"
PrintOut
Write-Output "Name after calling function : $name"Output
Enter your Name: PowerShell Name inside function : PowerShell Name after calling function : Alpha
As we observe here, $name variable value changes inside the function but doesn’t reflect the outside of the function because it has a limited scope.
Similarly, for the array,
$services = @()
function Automatic5Servc{
$services = Get-Service | Where{$_.StartType -eq "Automatic"} | Select -First 5
}
Automatic5Servc
Write-Output "Automatic Services : $services"In the above code, you won’t get the services information because the value of the Services array variable is null and function can’t update the original variable.
195 Views
