NAME
    Clear-Variable

SYNOPSIS
    Deletes the value of a Variable.

SYNTAX
    Clear-Variable [-Name] <string[]> [-Exclude <string[]>] [-Force] [-Include <string[]>] [-PassThru] [-Scope <string>] [-Confirm] [-WhatIf] [<CommonParameters>]

DESCRIPTION
    The Clear-Variable cmdlet deletes the data stored in a Variable, but it does not delete the Variable. As a result, the value of the Variable is NULL (empty). If the Variable has a specified data or object type, Clear-Variable preserves the type of the object stored in the Variable.

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

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

    -Force [<SwitchParameter>]
        Allows the cmdlet to clear a Variable even if it is read-only. Even using the Force parameter, the cmdlet cannot clear constants.

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

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

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

    -Name <string[]>
        Specifies the name of the Variable to be cleared. Wildcards are permitted. This parameter is required, but the parameter name (“Name”) is optional.

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

    -PassThru [<SwitchParameter>]
        Returns an object representing the cleared 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>
        Specifies the scope in which this Alias is valid. 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

    -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
    None
        You cannot pipe objects to Clear-Variable.

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

NOTES

        To delete a Variable, along with its value, use Remove-Variable or Remove-Item.

        Clear-Variable will not delete the values of Variables that are set as constants or owned by the system, even if you use the -Force parameter.

        If the Variable that you are clearing does not exist, the cmdlet has no effect. It does not create a Variable with a null value.

        You can also refer to Clear-Variable by its built-in Alias, “clv”. For more information, see about_aliases.

    ————————– EXAMPLE 1 ————————–

    C:\PS>Clear-Variable my* -global

    Description
    ———–
    This command deletes the value of the global Variables that begin with “my”.

    ————————– EXAMPLE 2 ————————–

    C:\PS>$a=3

    C:\PS>&{ Clear-Variable a }

    C:\PS>$a
    3

    Description
    ———–
    These commands demonstrate that clearing a Variable in a child scope does not clear the value in the parent scope. The first command sets the value of the Variable $a to “3”. The second command uses the invoke operator (&) to run a Clear-Variable command in a new scope. The Variable is cleared in the child scope (although it did not exist), but it is not cleared in the local scope. The third command, which gets the value of $a, shows that the value “3” is unaffected.

    ————————– EXAMPLE 3 ————————–

    C:\PS>Clear-Variable -Name processes

    Description
    ———–
    This command deletes the value of the $processes Variable. The $processes Variable still exists, but the value is null.

RELATED LINKS
    Online version: http://go.microsoft.com/fwlink/?LinkID=113285
    Get-Variable
    Set-Variable
    New-Variable
    Remove-Variable