Tag Archives: Visibility

cmdlet, Set, Variable

Set-Variable

NAME
    Set-Variable

SYNOPSIS
    Sets the value of a Variable. Creates the Variable if one with the requested name does not exist.

SYNTAX
    Set-Variable [-Name] <string[]> [[-Value] <Object>] [-Description <string>] [-Exclude <string[]>] [-Force] [-Include <string[]>] [-Option {None | ReadOnly | Constant | Private | AllScope}] [-PassThru] [-Scope <string>] [-Visibility {Public | Private}] [-Confirm] [-WhatIf] [<CommonParameters>]

DESCRIPTION
    The Set-Variable cmdlet assigns a value to a specified Variable or changes the current value. If the Variable does not exist, the cmdlet creates it.

PARAMETERS
    -Description <string>
        Specifies the description of the Variable.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Exclude <string[]>
        Omits the specified items. The value of this parameter qualifies the Path parameter. Enter a path element or pattern, such as “*.txt”. Wildcards are permitted.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Force [<SwitchParameter>]
        Allows you to create a Variable with the same name as an existing read-only Variable, or to change the value of a read-only Variable.

        By default, you can overwrite a Variable, unless the Variable has an option value of “ReadOnly” or “Constant”. For more information, see the Option parameter.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Include <string[]>
        Changes only the specified items. The value of this parameter qualifies the Name parameter. Enter a name or name pattern, such as “c*”. Wildcards are permitted.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Name <string[]>
        Specifies the Variable name.

        Required?                    true
        Position?                    1
        Default value
        Accept pipeline input?     true (ByPropertyName)
        Accept wildcard characters? false

    -Option <ScopedItemOptions>
        Changes the value of the Options property of the Variable. Valid values are:

        — None: Sets no options. (“None” is the default.)

        — ReadOnly: The properties of the Variable cannot be changed, except by using the Force parameter. You can use Remove-Variable to delete the Variable.

        — Constant: The Variable cannot be deleted and its properties cannot be changed. “Constant” is available only when you are creating an Alias. You cannot change the option of an existing Variable to “Constant”.

        — Private: The Variable is available only within the scope specified by the Scope parameter. It is inherited by child scopes.

        — AllScope: The Variable is copied to any new scopes that are created.

        To see the Options property of the Variables, type “Get-Variable| Format-Table -property name, options -autosize”.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -PassThru [<SwitchParameter>]
        Returns an object representing the new Variable. By default, this cmdlet does not generate any output.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Scope <string>
        Determines the scope of the Variable. Valid values are “Global”, “Local”, or “Script”, or a number relative to the current scope (0 through the number of scopes, where 0 is the current scope and 1 is its parent). “Local” is the default. For more information, see about_scopes.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Value <Object>
        Specifies the value of the Variable.

        Required?                    false
        Position?                    2
        Default value
        Accept pipeline input?     true (ByValue, ByPropertyName)
        Accept wildcard characters? false

    -Visibility <SessionStateEntryVisibility>
        Determines whether the Variable is visible outside of the session in which it was created. This parameter is designed for use in scripts and commands that will be delivered to other users.

        Valid values are:

        — Public: The Variable is visible. (“Public” is the default.)
        — Private: The Variable is not visible.

        When a Variable is private, it does not appear in lists of Variables, such as those returned by Get-Variable, or in displays of the Variable: drive. Commands to read or change the value of a private Variable return an error. However, the user can run commands that use a private Variable if the commands were written in the session in which the Variable was defined.

        Required?                    false
        Position?                    named
        Default value                Public
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Confirm [<SwitchParameter>]
        Prompts you for confirmation before executing the command.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -WhatIf [<SwitchParameter>]
        Describes what would happen if you executed the command without actually executing the command.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    <CommonParameters>
        This cmdlet supports the common parameters: Verbose, Debug,
        ErrorAction, ErrorVariable, WarningAction, WarningVariable,
        OutBuffer and OutVariable. For more information, type,
        “Get-Help about_CommonParameters“.

INPUTS
    System.Object
        You can pipe an object that represents the value of the Variable to Set-Variable.

OUTPUTS
    None or System.Management.Automation.PSVariable
        When you use the PassThru parameter, Set-Variable generates a System.Management.Automation.PSVariable object representing the new or changed Variable. Otherwise, this cmdlet does not generate any output.

NOTES

    ————————– EXAMPLE 1 ————————–

    C:\PS>Set-Variable -Name desc -Value “A description”

    C:\PS>Get-Variable -Name desc

    Description
    ———–
    These commands set the value of the “desc” Variable to “A description”, and then get the value of the Variable.

    ————————– EXAMPLE 2 ————————–

    C:\PS>Set-Variable -Name processes -Value (Get-Process) -Option constant -Scope global -Description “All processes” -PassThru | Format-List -property *

    Description
    ———–
    This command creates a global, read-only Variable that contains all processes on the system, and then it displays all properties of the Variable.

    The command uses the Set-Variable cmdlet to create the Variable. It uses the PassThru parameter to create an object representing the new Variable, and it uses the pipeline operator (|) to pass the object to the Format-List cmdlet. It uses the Property parameter of Format-List with a value of all (*) to display all properties of the newly created Variable.

    The value, “(Get-Process)”, is enclosed in parentheses to ensure that it is executed before being stored in the Variable. Otherwise, the Variable contains the words “Get-Process“.

    ————————– EXAMPLE 3 ————————–

    C:\PS># Set-Variable -Name counter -Visibility private

    C:\PS> New-Variable -Name counter -Visibility public -Value 26

    C:\PS> $counter
    26

    C:\PS> Get-Variable c*

    Name Value
    —- —–
    Culture en-US
    ConsoleFileName
    ConfirmPreference High
    CommandLineParameters {}
    Counter 26

    C:\PS> Set-Variable -Name counter -Visibility private

    C:\PS> Get-Variable c*

    Name Value
    —- —–
    Culture en-US
    ConsoleFileName
    ConfirmPreference High
    CommandLineParameters {}

    C:\PS> $counter
    “Cannot access the Variable ‘$counter’ because it is a private Variable”

    C:\PS> .\use-counter.ps1
    Commands completed successfully.

    Description
    ———–
    This command shows how to change the visibility of a Variable to “Private”. This Variable can be read and changed by scripts with the required permissions, but it is not visible to the user.

    The sample output shows the difference in the behavior of public and private Variables.

RELATED LINKS
    Online version: http://go.microsoft.com/fwlink/?LinkID=113401
    Get-Variable
    New-Variable
    Remove-Variable
    Clear-Variable

cmdlet, New, Variable

New-Variable

NAME
    New-Variable

SYNOPSIS
    Creates a new Variable.

SYNTAX
    New-Variable [-Name] <string> [[-Value] <Object>] [-Description <string>] [-Force] [-Option {None | ReadOnly | Constant | Private | AllScope}] [-PassThru] [-Scope <string>] [-Visibility {Public | Private}] [-Confirm] [-WhatIf] [<CommonParameters>]

DESCRIPTION
    The New-Variable cmdlet creates a new Variable in Windows PowerShell. You can assign a value to the Variable while creating it or assign or change the value after it is created.

    You can use the parameters of New-Variable to set the properties of the Variable (such as those that create read-only or constant Variables), set the scope of a Variable, and determine whether Variables are public or private.

    Typically, you create a new Variable by typing the Variable name and its value, such as “$var = 3”, but you can use the New-Variable cmdlet to use its parameters.

PARAMETERS
    -Description <string>
        Specifies a description of the Variable.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Force [<SwitchParameter>]
        Allows you to create a new Variable with the same name as an existing read-only Variable.

        By default, you can overwrite a Variable unless the Variable has an option value of ReadOnly or Constant. For more information, see the Option parameter.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Name <string>
        Specifies a name for the new Variable.

        Required?                    true
        Position?                    1
        Default value
        Accept pipeline input?     true (ByPropertyName)
        Accept wildcard characters? false

    -Option <ScopedItemOptions>
        Sets the value of the Options property of the new Variable.

        Valid values are:

        — None: Sets no options. (“None” is the default.)

        — ReadOnly: The value of the Variable cannot be changed except by using the Force parameter. You can use Remove-Variable to delete the Variable.

        — Constant: The Variable cannot be deleted, and its properties cannot be changed. “Constant” is available only when you are creating an Alias. You cannot change the option of an existing Variable to “Constant”.

        — Private: The Variable is available only within the scope specified by the Scope parameter. It is inherited by child scopes. (This value is not related to the “Private” value of the Visibility parameter.)

        — AllScope: The Variable is copied to any new scopes that are created.

        To see the Options property of the Variables, type “Get-Variable| Format-Table -property name, options -autosize”.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -PassThru [<SwitchParameter>]
        Returns an object representing the new Variable. By default, this cmdlet does not generate any output.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Scope <string>
        Determines the scope of the new Variable. Valid values are “Global”, “Local”, or “Script”, or a number relative to the current scope (0 through the number of scopes, where 0 is the current scope and 1 is its parent). “Local” is the default. For more information, see about_scopes.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Value <Object>
        Specifies the initial value of the Variable.

        Required?                    false
        Position?                    2
        Default value
        Accept pipeline input?     true (ByValue, ByPropertyName)
        Accept wildcard characters? false

    -Visibility <SessionStateEntryVisibility>
        Determines whether the Variable is visible outside of the session in which it was created. This parameter is designed for use in scripts and commands that will be delivered to other users.

        Valid values are:

        — Public: The Variable is visible. (“Public” is the default.)
        — Private: The Variable is not visible.

        When a Variable is private, it does not appear in lists of Variables, such as those returned by Get-Variable, or in displays of the Variable: drive. Commands to read or change the value of a private Variable return an error. However, the user can run commands that use a private Variable if the commands were written in the session in which the Variable was defined.

        Required?                    false
        Position?                    named
        Default value                Public
        Accept pipeline input?     false
        Accept wildcard characters? false

    -Confirm [<SwitchParameter>]
        Prompts you for confirmation before executing the command.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    -WhatIf [<SwitchParameter>]
        Describes what would happen if you executed the command without actually executing the command.

        Required?                    false
        Position?                    named
        Default value
        Accept pipeline input?     false
        Accept wildcard characters? false

    <CommonParameters>
        This cmdlet supports the common parameters: Verbose, Debug,
        ErrorAction, ErrorVariable, WarningAction, WarningVariable,
        OutBuffer and OutVariable. For more information, type,
        “Get-Help about_CommonParameters“.

INPUTS
    System.Object
        You can pipe a value to New-Variable.

OUTPUTS
    None or System.Management.Automation.PSVariable
        When you use the PassThru parameter, New-Variable generates a System.Management.Automation.PSVariable object representing the new Variable. Otherwise, this cmdlet does not generate any output.

NOTES

    ————————– EXAMPLE 1 ————————–

    C:\PS>New-Variable days

    Description
    ———–
    This command creates a new Variable named “days”. It has no value immediately following the command.

    ————————– EXAMPLE 2 ————————–

    C:\PS>New-Variable zipcode -Value 98033

    Description
    ———–
    This command creates a Variable named “zipcode” and assigns it the value “98033”.

    ————————– EXAMPLE 3 ————————–

    C:\PS>New-Variable -Name max -Value 256 -Option readonly

    New-Variable -Name max -Value 1024

    New-Variable -Name max -Value 1024 -Force

    C:\PS> New-Variable -Name max -Value 256 -Option readonly

    C:\PS> New-Variable -Name max -Value 1024
    New-Variable : A Variable with name ‘max’ already exists.
    At line:1 char:13
    + New-Variable <<<< -Name max -Value 1024

    C:\PS> New-Variable -Name max -Value 1024 -Force

    Description
    ———–
    This example shows how to use the ReadOnly option of New-Variable to protect a Variable from being overwritten.

    The first command creates a new Variable named Max and sets its value to “256”. It uses the Option parameter with a value of ReadOnly.

    The second command tries to create a second Variable with the same name. This command returns an error, because the read-only option is set on the Variable.

    The third command uses the Force parameter to override the read-only protection on the Variable. In this case, the command to create a new Variable with the same name succeeds.

    ————————– EXAMPLE 4 ————————–

    C:\PS>New-Variable -Name counter -Visibility private

    #Effect of private Variable in a module.

    C:\PS> Get-Variable c*

    Name                         Value
    —-                         —–
    Culture                        en-US
    ConsoleFileName
    ConfirmPreference             High
    CommandLineParameters         {}

    C:\PS> $counter
    “Cannot access the Variable ‘$counter’ because it is a private Variable”

    C:\PS> Get-Counter
    Name         Value
    —-         —–
    Counter1     3.1415
    …

    Description
    ———–
    This command demonstrates the behavior of a private Variable in a module. The module contains the Get-Counter cmdlet, which has a private Variable named “Counter”. The command uses the Visibility parameter with a value of “Private” to create the Variable.

    The sample output shows the behavior of a private Variable. The user who has loaded the module cannot view or change the value of the Counter Variable, but the Counter Variable can be read and changed by the commands in the module.

RELATED LINKS
    Online version: http://go.microsoft.com/fwlink/?LinkID=113361
    Get-Variable
    Set-Variable
    Remove-Variable
    Clear-Variable