Cloning in vb6 was always a pain. It was so easy to get the code wrong, and the problems it caused were endless - normally stack overflow.
In .Net you do not have to do any cloning any more - you can simply serialise the object and then copy it into the target object. The technique is quite widely used and described - but it is interesting to use it with generics, as it means that you can use it anywhere in your application. Here is a code sample showing what to do:
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Public Function CloneObject(Of T)(ByVal obj As T) As T
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Try
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Dim stream As New MemoryStream(1024)
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Dim formatter As New BinaryFormatter()
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formatter.Serialize(stream, obj)
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stream.Seek(0, SeekOrigin.Begin) ' go back to the start
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CloneObject = DirectCast(formatter.Deserialize(stream), T) 'get new object
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stream.Close() ' clear down the memory
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Catch excGeneric As Exception
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ReportException(excGeneric)
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End Try
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End Function
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You have to change your class declarations to be serializable to use this code:
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<Serializable()> Friend Class ChargeUnitType
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The call to clone any object looks similar to this:
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Dim objClonedType As ChargeUnitType = CloneObject(ChargeUnitType)
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Occasionally, for reasons I do not understand, the code fails on trying to deserialize, but for these cases, on the advice of Microsoft, I have included the following code in the object being serialized, and the problem has gone away:
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Friend Sub New(ByVal info As SerializationInfo, ByVal context As StreamingContext)
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MyBase.New(info, context)
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End Sub
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