Scope

Own root scope. For more information, see theModules section of this article.When a child scope is created, it includes all the aliases and variables thathave the AllScope option, and some automatic variables. This option isdiscussed later in this article.Unless you explicitly make the items private, the items in the parent scope areavailable to the child scope. Items that you create or change in a child scopedon't affect the parent scope, unless you explicitly specify the scope when youcreate the items.To find the items in a particular scope, use the Scope parameter ofGet-Variable or Get-Alias.For example, to get all the variables in the local scope, type:Get-Variable -Scope localTo get all the variables in the global scope, type:Get-Variable -Scope globalWhen a reference is made to a variable, alias, or function, PowerShell searchesthe current scope. If the item isn't found, the parent scope is searched. Thissearch is repeated all they way up to the global scope. If a variable isprivate in a parent scope, the search through continues through the scopechain. Example 4 shows the effect of a private variable in a scopesearch.PowerShell scopes namesPowerShell defines names for some scopes to allow easier access to that scope.PowerShell defines the following named scopes:Global: The scope that's in effect when PowerShell starts or when youcreate a new session or runspace. Variables and functions that are presentwhen PowerShell starts, such as automatic variables and preference variables,are created in the global scope. The variables, aliases, and functions inyour PowerShell profiles are also created in the global scope. The globalscope is the root parent scope in a runspace.Local: The current scope. The local scope can be the global scope or anyother scope.Script: The scope that's created while a script file runs. The commandsin the script run in the script scope. For the commands in a script, thescript scope is the local scope.For cmdlets that support scopes, scopes can be referred to by a number thatdescribes the relative position of one scope to another. Scope 0 denotes thecurrent (local) scope, scope 1 is the current scope's parent, scope 2 is thecurrent scope's grandparent. This pattern continues until you reach the rootscope.Scope modifiersA variable, alias, or function name can include any one of the followingoptional scope modifiers:global: - Specifies that the name exists in the Global scope.local: - Specifies that the name exists in the Local scope. The currentscope is always the Local scope.private: - Specifies that the name is

In your session that have a Scope parameter:Get-Help * -Parameter scopeTo find the variables that are visible in a particular scope, use the Scopeparameter of Get-Variable. The visible variables include global variables,variables in the parent scope, and variables in the current scope.For example, the following command gets the variables that are visible in thelocal scope:Get-Variable -Scope localTo create a variable in a particular scope, use a scope modifier or theScope parameter of Set-Variable. The following command creates a variablein the global scope:New-Variable -Scope global -Name a -Value "One"You can also use the Scope parameter of the New-Alias, Set-Alias, orGet-Alias cmdlets to specify the scope. The following command creates analias in the global scope:New-Alias -Scope global -Name np -Value Notepad.exeTo get the functions in a particular scope, use the Get-Item cmdlet when youare in the scope. The Get-Item cmdlet doesn't have a Scope parameter.NoteFor the cmdlets that use the Scope parameter, you can also refer toscopes by number. The number describes the relative position of one scope toanother. Scope 0 represents the current, or local, scope. Scope 1 indicatesthe immediate parent scope. Scope 2 indicates the parent of the parent scope,and so on. Numbered scopes are useful if you have created many recursivescopes.Using dot-source notation with scopeScripts and functions follow the rules of scope. You create them in aparticular scope, and they affect only that scope unless you use a cmdletparameter or a scope modifier to change that scope.But, you can add the contents of a script or function to the current scopeusing dot-source notation. When you run a script or function using dot-sourcenotation, it runs in the current scope. Any functions, aliases, and variablesin the script or function are added to the current scope.For example, to run the Sample.ps1 script from the C:\Scripts directory inthe script scope (the default for scripts), just enter the full path to thescript file on the command line.c:\scripts\sample.ps1A script file must have a .ps1 file extension to be executable. Files thathave spaces in their path must be enclosed in quotes. If you try to execute thequoted path, PowerShell displays the contents of the quoted string instead ofrunning the script. The call operator (&) allows you to execute the contentsof the string containing the filename.Using the call operator to run a function or script runs it in script scope.Using the call operator is no different than running the script by name.& c:\scripts\sample.ps1You can read more about

Private and only visible to thecurrent scope.Noteprivate: isn't a scope. It's an option that changes theaccessibility of an item outside of the scope in which it's defined.script: - Specifies that the name exists in the Script scope.Script scope is the nearest ancestor script file's scope or Global ifthere is no nearest ancestor script file.using: - Used to access variables defined in another scope while runningin remote sessions, background jobs, or thread jobs.workflow: - Specifies that the name exists within a workflow. Note:Workflows aren't supported in PowerShell v6 and higher. - A modifier created by a PowerShell PSDriveprovider. For example:NamespaceDescriptionAlias:Aliases defined in the current scopeEnv:Environment variables defined in the current scopeFunction:Functions defined in the current scopeVariable:Variables defined in the current scopeThe default scope for scripts is the script scope. The default scope forfunctions and aliases is the local scope, even if they're defined in ascript.Using scope modifiersTo specify the scope of a new variable, alias, or function, use a scopemodifier.The syntax for a scope modifier in a variable is:$[:] = The syntax for a scope modifier in a function is:function [:] {}The following command, which doesn't use a scope modifier, creates a variablein the current or local scope:$a = "one"To create the same variable in the global scope, use the scope global:modifier:$global:a = "one"Get-Variable a | Format-List *Notice the Visibility and Options property values.Name : aDescription :Value : oneVisibility : PublicModule :ModuleName :Options : NoneAttributes : {}Compare that to a private variable:$private:pVar = 'Private variable'Get-Variable pVar | Format-List *Using the private scope modifier sets the Options property to Private.Name : pVarDescription :Value : Private variableVisibility : PublicModule :ModuleName :Options : PrivateAttributes : {}To create the same variable in the script scope, use the script: scopemodifier:$script:a = "one"You can also use a scope modifier with functions. The following functiondefinition creates a function in the global scope:function global:Hello { Write-Host "Hello, World"}You can also use scope modifiers to refer to a variable in a different scope.The following command refers to the $test variable, first in the local scopeand then in the global scope:$test$global:testThe using: scope modifierUsing is a special scope modifier that identifies a local variable in a remotecommand. Without a modifier, PowerShell expects variables in remote commands tobe defined in the remote session.The using scope modifier is introduced in PowerShell 3.0.For any script or command that executes out of session, you need the usingscope modifier to embed variable values from the calling