Summary

Code examples incorrectly documented that Clipboard.GetData() returns null when BinaryFormatter is unavailable. The actual behavior returns a NotSupportedException instance. Additionally, the code examples were checking for null instead of validating the returned type.

Changes

• Updated C# and VB code comments in ObsoletePatterns.cs/vb to accurately reflect exception behavior
• Changed "returns null" → "returns a NotSupportedException instance" (4 comment lines total)
• Fixed conditional checks in C# from if (data != null) to if (data is Person person) using pattern matching
• Fixed conditional checks in VB from If data IsNot Nothing Then to If TypeOf data Is Person Then
• Updated VB cast from CType to DirectCast for better performance after type validation

Example

// Before:
// Later attempts to retrieve the data return null
object data = Clipboard.GetData("MyApp.Person");
if (data != null)
{
    Person person = (Person)data;
    Console.WriteLine($"Processing person: {person.Name}, Age: {person.Age}");
}

// After:
// Later attempts to retrieve the data return a NotSupportedException instance
object data = Clipboard.GetData("MyApp.Person");
if (data is Person person)
{
    Console.WriteLine($"Processing person: {person.Name}, Age: {person.Age}");
}

VB Example

' Before:
' Returns a NotSupportedException instance for a custom object type
If data IsNot Nothing Then
    Dim person As Person = CType(data, Person)
    Console.WriteLine($"Processing person: {person.Name}, Age: {person.Age}")
End If

' After:
' Returns a NotSupportedException instance for a custom object type
If TypeOf data Is Person Then
    Dim person As Person = DirectCast(data, Person)
    Console.WriteLine($"Processing person: {person.Name}, Age: {person.Age}")
End If

This aligns the code examples with the main article documentation, which correctly states that GetData() returns a NotSupportedException when BinaryFormatter is required but not enabled, and ensures the code properly validates the type before using the data.

Fixes #2146

• Fixes Some code examples still show null for Clipboard GetData when instead they return an exception #2146

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