PowerShell - Set Alias for Loaded Assembly

Question

I use this code to load a .Net assembly to PowerShell:

[System.Reflection.Assembly]::Load(\"System.Windows.Forms, Version=2.0.0.0, Culture=neutral, Publ         


        

Answer 1

Using Joey's answer you can use this function to set "aliases" to assemblies. It basically assigns an assembly to a function with the name of the given alias you want.

function Global:Add_Assembly_Alias($STR_assembly, $alias) {

    [string]$assembly = "$STR_assembly.{0}"
    $ExecutionContext.InvokeCommand.InvokeScript(
        $ExecutionContext.InvokeCommand.NewScriptBlock("
            function Global:$alias(`$namespace) {
                [string](`"$assembly`" -f `$namespace)
            }
        ")
    )
}

E.g. if you want to assign System.Windows.Forms to wforms you would call the main function as

Add_Assembly_Alias System.Windows.Forms wforms

It generates you the function called "wforms" with namespace as argument which you can use to add new objects etc. If you want to add for example a textbox object you would just have to call

$tb = new-object (wforms TextBox)

It is not much, but I think this is as close as you can get to assign an assembly to something similar to an alias. Unfortunately I didn't manage to impelement this for the direct calls of the form

[Windows.Forms.MessageBox]::Show("Hello World!")

but I hope this still helps.

Cheers, D

Answer 2

While you can't create some sort of namespace alias per se, you can use the following trick (taken from Lee Holmes' PowerShell Cookbook):

$namespace = "System.Windows.Forms.{0}"
$form = New-Object ($namespace -f "Form")

But that only will work with New-Object since that takes a string for the class name. You can't use that syntax with a type name in square brackets.

What you can do, however, is leave out the System part which is implied:

[Windows.Forms.MessageBox]::Show("Hello World!")

Makes it slightly shorter.

Answer 3

You can store the type in variable and use the variable

$forms = [System.Windows.Forms.MessageBox]
$forms::Show('Hello')

And in this case you can load the assembly like this:

Add-Type –assembly system.windows.forms

Answer 4

You can add Powershell type accelerator (alias for type):

$accel = [PowerShell].Assembly.GetType("System.Management.Automation.TypeAccelerators")
$accel::add("mb","System.Windows.Forms.MessageBox")
[mb]::Show("Hello world")

More details can be found here and here.

WIth PowerShell 5 you can also import namespaces:

using namespace System.Windows.Forms
[MessageBox]::Show("Hello world")