7zip.ps1

Function Set-Default_2([String]$Ext, [String]$Value)
{
	$Classes = "HKLM:\SOFTWARE\Classes\"
	$Path = Join-Path -Path $Classes -ChildPath $Ext
	If (!(Test-Path -Path $Path))
	{
		New-Item -Path $Path
	}
	Set-ItemProperty -Path $Path -Name "(Default)" -Type String -Force -Value ($Value + $Ext)
}

Function Set-Handler($Extension)
{
	$Classes = "HKLM:\SOFTWARE\Classes\"
	$DefaultPath = "C:\Program Files\7-Zip\"
	$DefaultCommand = """" + $DefaultPath + "7zFM.exe"" ""%1"""

	$Handler = Join-Path -Path $Classes -ChildPath ($Value + $Extension["Ext"])
	If (!(Test-Path -Path $Handler))
	{
		New-Item -Path $Handler
	}
	Set-ItemProperty -Path $Handler -Name "(Default)" -Type String -Value $Extension["Description"]

	$DefaultIcon = Join-Path -Path $Handler -ChildPath "DefaultIcon"
	If (!(Test-Path -Path $DefaultIcon))
	{
		New-Item -Path $DefaultIcon
	}
	Set-ItemProperty -Path $DefaultIcon -Name "(Default)" -Type String -Value ($DefaultPath + $Extension["DefaultIcon"])
	
	$Command = Join-Path -Path $Handler -ChildPath "shell\open\command"
	If (!(Test-Path -Path $Command))
	{
		New-Item -Force -Path $Command
	}
	Set-ItemProperty -Path $Command -Name "(Default)" -Type String -Value $DefaultCommand
}

$001 = @{
    Ext = '.001'
	Description = '001 Archive'
    DefaultIcon = '7z.dll,9'
}

$7z = @{
	Ext = ".7z"
	Description = "7z Archive"
	DefaultIcon = "7z.dll,0"
}

$bzip2 = @{
	Ext = ".bzip2"
	Description = "bzip2 Archive"
	DefaultIcon = "7z.dll,2"
}

$zip = @{
	Ext = ".zip"
	Description = "Zip Archive"
	DefaultIcon = "7z.dll,1"
}

$rar = @{
	Ext = ".rar"
	Description = "RAR Archive"
	DefaultIcon = "7z.dll,3"
}

$cab = @{
	Ext = ".cab"
	Description = "CAB Archive"
	DefaultIcon = "7z.dll,7"
}

$iso = @{
	Ext = ".iso"
	Description = "ISO Image"
	DefaultIcon = "7z.dll,8"
}

<#
$ = @{
	Ext = ""
	Description = ""
	DefaultIcon = ""
}
#>

$Value = "7-Zip"
$Extensions = @($001, $7z, $bzip2, $zip, $rar, $cab, $iso)

ForEach ($Extension in $Extensions)
{
	Set-Default_2 -Ext $Extension["Ext"] -Value $Value
	Set-Handler -Extension $Extension
}