rspec/rules/S4210/vbnet/rule.adoc

== Why is this an issue?

When an assembly uses Windows Forms (classes and interfaces from the ``++System.Windows.Forms++`` namespace) its entry point should be marked with the ``++STAThreadAttribute++`` to indicate that the threading model should be "Single-Threaded Apartment" (STA) which is the only one supported by Windows Forms.


This rule raises an issue when the entry point (``++Shared Sub Main++`` method) of an assembly using Windows Forms is not marked as STA.

=== Noncompliant code example

[source,vbnet]
----
Imports System.Windows.Forms

Public Class Foo
  Shared Sub Main()
    Dim winForm As Form = New Form
    Application.Run(winForm)
  End Sub
End Class
----

=== Compliant solution

[source,vbnet]
----
Imports System.Windows.Forms

Public Class Foo
  <STAThread()> Shared Sub Main()
    Dim winForm As Form = New Form
    Application.Run(winForm)
  End Sub
End Class
----
ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

include::../message.adoc[]

endif::env-github,rspecator-view[]