$cs.Reg_GetExpandString

Description

Reads a REG_EXPAND_SZ registry value. Environment variables in the stored value, such as %ProgramFiles% or %SystemRoot%, are expanded before the value is returned. Returns an empty string if the value isn’t found.

The variables are expanded with the environment of the account that runs the PowerPack, which is SYSTEM. User-specific variables therefore point to the SYSTEM profile — for example, %USERPROFILE% becomes C:\Windows\system32\config\systemprofile. If you need the raw, unexpanded string, read it with PowerShell instead: (Get-Item 'HKLM:\SOFTWARE\Contoso\AppSuite').GetValue('DisplayIcon', $null, 'DoNotExpandEnvironmentNames').

Syntax

$cs.Reg_GetExpandString(string registryroot, string regkey, string regvalue)

Parameters

registryroot (String)

Root hive: HKLM/HKEY_LOCAL_MACHINE, HKCU/HKEY_CURRENT_USER, or HKU/HKEY_USERS. PowerPacks run as SYSTEM, so HKCU is the SYSTEM account’s hive, not the logged-on user’s. To change user settings, see Invoke-RunAsLoggedOnUser.

regkey (String)

Registry key path containing the value, relative to registryroot.

regvalue (String)

Name of the value to retrieve. Pass "" for the key’s default value.

Return value

String — the value with environment variables expanded. Empty string "" if the value isn’t found.

Example

PowerShell

$defaultPath = $cs.Reg_GetExpandString("HKU", ".DEFAULT\Environment", "Path")
$cs.Job_WriteLog("PATH of the default profile: $defaultPath")

Reading an uninstall string that contains a %ProgramFiles% reference. The returned value already contains the full path, so it can be used directly.

$uninstallString = $cs.Reg_GetExpandString('HKLM', 'SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\Contoso AppSuite', 'UninstallString')
$cs.Job_WriteLog("Resolved uninstall command: $uninstallString")

Reading a DisplayIcon value that references %SystemRoot%, to confirm the target file actually exists on disk.

$iconPath = $cs.Reg_GetExpandString('HKLM', 'SOFTWARE\Contoso\AppSuite', 'DisplayIcon')
if (-not (Test-Path $iconPath))
{
    $cs.Job_WriteLog("Warning: DisplayIcon target not found at $iconPath")
}

$cs.Reg_SetExpandString $cs.Reg_GetString