Powershell Classes - ReadOnly Properties

AddPublicMember.ps1

hidden AddPublicMember() {
    $Members = $this | Get-Member -Force -MemberType Property -Name '_*'
    ForEach ($Member in $Members) {
        $PublicPropertyName = $Member.Name -replace '_', ''
        # Define getter part
        $Getter = "return `$this.{0}" -f $Member.Name
        $Getter = [ScriptBlock]::Create($Getter)
        # Define setter part
        $Setter = "Write-Warning 'This is a readonly property.'"
        $Setter = [ScriptBlock]::Create($Setter)

        $AddMemberParams = @{
            Name = $PublicPropertyName
            MemberType = 'ScriptProperty'
            Value = $Getter
            SecondValue = $Setter
        }
        $this | Add-Member @AddMemberParams
    }
}

DeathStarClass.ps1

Class DeathStar {
    [String]$Class = 'Space battle station'
    [Int]$Width = '160000'
    [String[]]$HyperDriveRating = @('Class 4', 'Class 20')
    $Crew = @{
        ImperialNavy = 342953
        Stormtroopers = 25984
    }
    hidden [String]$_Ready = $null

    hidden AddPublicMember() {
        $Members = $this | Get-Member -Force -MemberType Property -Name '_*'
        ForEach ($Member in $Members) {
            $PublicPropertyName = $Member.Name -replace '_', ''
            # Define getter part
            $Getter = "return `$this.{0}" -f $Member.Name
            $Getter = [ScriptBlock]::Create($Getter)
            # Define setter part
            $Setter = "Write-Warning 'This is a readonly property.'"
            $Setter = [ScriptBlock]::Create($Setter)

            $AddMemberParams = @{
                Name = $PublicPropertyName
                MemberType = 'ScriptProperty'
                Value = $Getter
                SecondValue = $Setter
            }
            $this | Add-Member @AddMemberParams
        }
    }

    DeathStar () {
        $this.AddPublicMember()
        $this._Ready = $true
    }

    DeathStar ([int]$ImperialNavy, [int]$Stormtroopers) {
        $this.AddPublicMember()
        $this.Crew.ImperialNavy = $ImperialNavy
        $this.Crew.StormTroopers = $Stormtroopers
        $this._Ready = $true
    }
}