Functions/Get-RegistryKeyValue.ps1

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

function Get-RegistryKeyValue
{
    <#
    .SYNOPSIS
    Gets the value from a registry key.
     
    .DESCRIPTION
    PowerShell's `Get-ItemProperty` cmdlet is a pain to use. It doesn't actually return an object representing a registry key's value, but some other weird object that requires painful gyrations to get values from. This function returns just the value of a key.
     
    .EXAMPLE
    Get-RegistryKeyValue -Path 'hklm:\Software\Carbon\Test' -Name 'Title'
     
    Returns the value of the 'hklm:\Software\Carbon\Test' key's `Title` value.
    #>

    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]
        # The path to the registry key where the value should be set. Will be created if it doesn't exist.
        $Path,
        
        [Parameter(Mandatory=$true)]
        [string]
        # The name of the value being set.
        $Name
    )
    
    Set-StrictMode -Version 'Latest'

    Use-CallerPreference -Cmdlet $PSCmdlet -Session $ExecutionContext.SessionState

    if( -not (Test-RegistryKeyValue -Path $Path -Name $Name) )
    {
        return $null
    }
    
    $itemProperties = Get-ItemProperty -Path $Path -Name *
    $value = $itemProperties.$Name
    Write-Debug -Message ('[{0}@{1}: {2} -is {3}' -f $Path,$Name,$value,$value.GetType())
    return $value
}