Для вашего URI просмотрите элементы или форму, указав c элементы.
$url = 'https://en.m.wikipedia.org/wiki/PowerShell'
($FormElements = Invoke-WebRequest -Uri $url -SessionVariable fe)
<#
# Results
StatusCode : 200
StatusDescription : OK
Content : <!DOCTYPE html>
<html class="client-nojs" lang="en" dir="ltr">
<head>
...
#>
$FormElements.AllElements
<#
# Results
innerHTML :
innerText :
outerHTML :
outerText :
tagName : !
innerHTML : <HEAD><TITLE>PowerShell - Wikipedia</TITLE>
<META charset=UTF-8>
<SCRIPT>document.documentElement.className="client-js
...#>
$FormElements.ParsedHtml.anchors | Select 'ie8_href'
<#
# Results
ie8_href
--------
about:/w/index.php?title=Special:UserLogin&returnto=PowerShell
about:/w/index.php?title=PowerShell&action=edit§ion=0
about://en.wikipedia.org/w/index.php?title=PowerShell&mobileaction=toggle_view_desktop
#>
($Form = $FormElements.Forms[0]) | Format-List -Force
<#
# Results
Id :
Method : get
Action : /w/index.php
Fields : {[main-menu-input, on], [searchInput, ]}
#>
$Form | Get-Member
<#
# Results
TypeName: Microsoft.PowerShell.Commands.FormObject
Name MemberType Definition
---- ---------- ----------
Equals Method bool Equals(System.Object obj)
GetHashCode Method int GetHashCode()
GetType Method type GetType()
ToString Method string ToString()
Action Property string Action {get;}
Fields Property System.Collections.Generic.Dictionary[string,string] Fields {get;}
Id Property string Id {get;}
Method Property string Method {get;}
#>
$Form.Fields
<#
# Results
Key Value
--- -----
main-menu-input on
searchInput
#>