Is there any technique available for copying one object of class A to another object of class B ?

[Nadia Monalisa]

Hi, Thanks for your reply. Actually, my classes are auto generated and I dont have control over them. I mean, my class A is a LINQ to SQL model generated from the dbml file, and class B is a proxy class for a WCF Service. Yeah, I can manipulate those classes manually but it will be hard to maintain when I will update my service reference or dbml file. So, I was looking for some other technique that can take an object of class A and return object of class B where all properties of A is copied to B.

[nlarson11]

ah. i would just use reflection then. get all the properites available from class A and then go through all the properties of class B. if there is a match then copy the data from A to B.

'Never argue with an idiot; they'll drag you down to their level and beat you with experience.' ~ anonymous

[Nadia Monalisa]

Thanks again. I am not familiar with Reflection. Would you please give me any example snippet Or point me to an article which shows how to do this task as you mentioned ?

[nlarson11]

Forgive...i'm a lowly VB programmer and i just quickly threw this together - so translate it and it should do what your looking for

Imports System.Reflection

Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim a As New TheFromClass With {.Hello = "hello there", .Name = "myclass"}
Dim b As New TheToClass With {.GoodBye = "later dude", .Hello = "wuzup"}

    Dim ta As Type = GetType(TheFromClass)
    Dim tb As Type = GetType(TheToClass)

    Dim obj As Object, PropertyName As String, ToPI As PropertyInfo = Nothing

    MsgBox(b.Hello)

    For Each FromPI As PropertyInfo In ta.GetProperties
        PropertyName = FromPI.Name
        obj = FromPI.GetValue(a, Nothing)

        ToPI = tb.GetProperties.Where(Function(p) p.Name = PropertyName).FirstOrDefault

        If ToPI IsNot Nothing Then ToPI.SetValue(b, obj, Nothing)
    Next

    MsgBox(b.Hello)

    End
End Sub

End Class

Public Class TheFromClass
Public Property Hello As String
Public Property Name As String
End Class

Public Class TheToClass
Public Property GoodBye As String
Public Property Hello As String
End Class

'Never argue with an idiot; they'll drag you down to their level and beat you with experience.' ~ anonymous

[Nadia Monalisa]

Thanks a loooooooooooooot. I highly appreciate. Yes, I know some online VB to C# converter, so this code will be fine. :) Regards.

[Giorgi Dalakishvili]

You can use Binary Serialization[^]

Giorgi Dalakishvili #region signature My Articles Browsing xkcd in a windows 7 way[^] #endregion

[Bernhard Hiller]

Try this:

    public static void CopyFields(object source, object target)
    {
        if (source == null)
            throw new ArgumentNullException("source");
        if (target == null)
            throw new ArgumentNullException("target");

        //loop through source object
        FieldInfo\[\] fiSource = source.GetType().GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
        FieldInfo\[\] fiTarget = target.GetType().GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
        foreach (FieldInfo fiS in fiSource)
        {
            //check if that field exists in target
            foreach (FieldInfo fiT in fiTarget)
            {
                if (fiT.Name == fiS.Name)
                {
                    //copy value
                    fiT.SetValue(target, fiS.GetValue(source));
                    //stop inner loop
                    break;
                }
            }
        }
    }

Then call CopyFields(a, b).

[Nadia Monalisa]

Hi Bhiller, Thank you soooo much.. Your code will be highly useful for me. I just checked your code and awesome!! Great !! Thats the solution what I was searching for so loooong time. Many many thanks.

modified on Friday, August 6, 2010 2:49 AM

[Lukasz Nowakowski]

I don't know how it works for LINQ to SQL model, but once I did something like this for Entity Framework model. For web application there was supposed to be a WCF server, that was interacting with database with help of EF. And web application wasn't supposed to reference EF libraries (cause there should be separation) and I had to do mapping between EF classes an POCO classes. And to do it I used tt scripts. They are used to generate files (different kinds of them). And with those scripts I also created some mapper, that created mappings for each class defined in the model. Maybe you can find something like this for LINQ to SQL (unfortunately I don't have time to search for it, and looking at TODO list wan't have in the nearest future).

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[PIEBALDconsult]

I would cache the information to make repeated calls quicker.

[il_manti]

Hi, This is looking great. Quick question, is there any way to modify this code to allow for inner class conversions too? My classes have inner classes and these too differ by name space. I have no idea how reflection works so if you could be kind enough to point out a solution for me it would be great. If not, I'll try to figure it out :/ Thanks a lot for your time.

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