Mastering Windows PowerShell Scripting - Third Edition

Fabricating objects

Objects with specific properties can be simulated by creating a PS custom object (or PSObject):

[PSCustomObject]@{ 
    Property = "Value" 
} 

Methods can be added to an object using Add-Member:

[PSCustomObject]@{} | Add-Member MethodName -MemberType ScriptMethod -Value { } 

This approach can be extended to include objects instantiated by New-Object. The following function creates and uses instances of two different .NET types:

function Write-File {    $fileStream = New-Object System.IO.FileStream(        "C:\Temp\test.txt",        'OpenOrCreate'    )    $streamWriter = New-Object System.IO.StreamWriter($fileStream)    $streamWriter.WriteLine("Hello world")    $streamWriter.Close()}

The following mocks replace the first call made to New-Object in the preceding ...