Converting VBScript's Public Statement
Definition: Declares public variables and allocates storage space. Declares, in a Class block, a private variable.
Windows PowerShell enables you to create a global (public) variable simply by specifying the scope when you create the variable. For example, this command creates a variable named $a with the scope set to Global. Note that, when specifying a scope, you do not preface the variable name with a $; however, the variable will, in fact, be named $a.
$Global:a = 199
Here’s an interesting use for global variables. Start up Windows PowerShell, but do not declare the variable $a. Instead, put the preceding line of code in a script (e.g., test.ps1), run the script, and then type $a from the command prompt. You should get back the following:
Because this is a global variable, it’s available in scripts, in the command shell, and in any other scope. Cool, huh?
Note. Admittedly, this isn’t quite the same as what the Public statement does in VBScript; that’s because the VBScript statement is concerned with classes, and we aren’t discussing Windows PowerShell classes in this introductory series. Therefore we’ve extended the definition of “public” to include Windows PowerShell scopes. That gives us a chance to talk about the Windows PowerShell global variables, which we find very cool.