Question

I have custom class like the below;

Public MyClass
  Public Property MyText() As String
End Class

Then in my code page I have the following VB.NET code;

Dim obj1 As New MyClass
Dim obj2 As New MyClass

obj1 = obj2
obj1.MyText = "Test"

My problem is that when the below piece of code is executed the obj2.MyText is updated as well. How can I avoid this?

obj1.MyText = "Test"

Thanks.

Answer 1

This is the problem:

obj1 = obj2

That copies the value of obj2 to obj1. That value is not the object – it’s a reference to the object. So now obj1 and obj2 refer to the same object, so any changes you make via one variable will be seen by the other.

I realize this is VB rather than C#, but you may still find my article on reference types and value types useful. Fundamentally, you need to grok how reference types behave.