Vb. NET ByVal and ByRef--byval with a shallow copy and a deep copy

Beginner vb.net, sum up ByVal and ByRef

1 pass through the ByVal variables, VB. NET duplicates a new variable that is equal to the source value. And ByRef is the equivalent of a reference.
For example, when we learn C, we get the swap () function


Imports System
' Test that Can ' t Swap A and B
Class MyApp
Public Shared Sub Main ()
Dim A as Integer = 0
Dim B as Integer = 1
Console.WriteLine ("Source:a" & A & "B" & B)
Fakeswap (a,b) ' After this fakeswap (a,b), A still are 0 and B still is 1
Console.WriteLine ("After Fakeswap:a" & A & "B" & B)
Swap (a,b) ' After this swap (A,B), A are 1 and B is 0
Console.WriteLine ("After Swap:a" & A & "B" & B)
End Sub

' Fake Swap Function:fakeswap ()
Shared Sub Fakeswap (ByVal InA As Integer, ByVal InB As Integer)
Dim TMP as Integer
TMP = InA
InA = InB
InB = TMP
End Sub
' Real Swap Function:swap ()
Shared Sub Swap (ByRef InA As Integer, ByRef InB As Integer)
Dim TMP as Integer
TMP = InA
InA = InB
InB = TMP
End Sub
End Class




2 Note: If ByVal passes An instance of a custom class, only the reference to that instance is replicated, and the resource to which the reference is directed is not replicated. --equivalent to a shallow copy in C + +.


Imports System

An instance of class A mya as a parameter of the function testa (ByVal InA as A), the result should be
'--passed by value to a shallow copy, just a copy of the instance referencing--a Mya and Ina share a resource
Class MyApp
Public Shared Sub Main ()
Dim MyA as A
Console.WriteLine ("The Original Resource of MyA is:" & Mya.resource)
' Call Testa ()
Testa (MyA)
Console.WriteLine ("After called" The ByVal Fun, the resource of MyA is: "& Mya.resource)
End Sub
' Function testa () Mya by value in order to change INA resource, in fact, the modification is also MYA resource
Shared Sub Testa (ByVal InA as A)
Ina.resource = 1
End Sub
End Class

' Class A has resource resource (integer)
Class A
Public Resource as Integer = 0
End Class




3 If you want to implement the "by value" (deep copy) of an instance of a class (not a reference), you must overridde the Clone () method or have a copy constructor specifically?
Method One:
<serializable>_
Class ABC
Xxx
End Class

Then use MemoryStream and BinaryFormatter (Streamcontext to use the file type), which is definitely a deep copy. But how do you implement a "copy construct" in C + +?
Cond...