how to execute code after deserializing a custom component?

Question

I am trying to implement a method that get's called on deserializing a custom component.
However, the methods marked as OnDeserializing and OnDeserialized are never called.

I found this question on SO and from the text I conclude that here these method's are being called. So I compared this code with mine.
Also in the documentation I cannot see anything that I am missing.

What I need is that when my custom component is deserializing from the Designer.cs on designtime, I can step in and do some extra coding.

So what am I missing here ?

[Serializable]
public partial class gttDataTable : Component, ISerializable
{
    private Collection<ConfigColumn> _columns = new Collection<ConfigColumn>();

    public gttDataTable()
    { }

    public gttDataTable(SerializationInfo info, StreamingContext context)
    { }

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public Collection<ConfigColumn> gttColumns
    {
        get { return _columns; }
        set { _columns = value; }
    }

    [OnDeserializing]
    internal void OnDeserializingMethod(StreamingContext context)
    {
        // this code is never called
        throw new NotImplementedException();
    }

    [OnDeserialized]
    internal void OnDeserializedMethod(StreamingContext context)
    {
        // this code is never called
        throw new NotImplementedException();
    }

    public void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        // this code is never called
        throw new NotImplementedException();
    }
    
    private IComponentChangeService GetChangeService()
    {
        return (IComponentChangeService)GetService(typeof(IComponentChangeService));
    }
}

public class ConfigColumn
{
    public string Name { get; set; }
    public string Caption { get; set; }
    public string ColumnName { get; set; }
    public Type DataType { get; set; }
}

EDIT
For clarity, the problem is that both the internal methods are never called when the custom component is deseriazeling.

EDIT 2
I tried making the internal methods public, as suggested, but it makes no difference. They still are not called

EDIT 3
I read this link and doublechecked that all is the same as in the documetation. In my opinion it is all correct, but still the methods are not called

I got methods called for the provided code as expected. Both `ing` and `ed` What is the problem ? Did you need help to implement desierialization instead of throwing not implemented ? Did you need to test if the component is in design time and not in run time ? Also you must know that `Collection` is not serializable by default. — , Jan 29 '21 at 12:06
Does this answer your question? [Can't get my custom control to serialize from the designer](https://stackoverflow.com/questions/65883434/cant-get-my-custom-control-to-serialize-from-the-designer) and [Can't get my custom control to serialize from the designer](https://stackoverflow.com/questions/65883434/cant-get-my-custom-control-to-serialize-from-the-designer) and [.NET Deserialisation with OnDeserializing and OnDeserialized](https://stackoverflow.com/questions/18377046/net-deserialisation-with-ondeserializing-and-ondeserialized) — , Jan 29 '21 at 12:10
[Custom serialization](https://learn.microsoft.com/dotnet/standard/serialization/custom-serialization) — , Jan 29 '21 at 12:12
@Rekshino What do you mean ? I guess the serializer from VS ? It's a custom component dropped on a form and the serializing is done on designtime by the editor of VS — GuidoG, Jan 29 '21 at 12:26
@OlivierRogier The collection is properly serialized, that is not the problem. My problem is exact as in the question, why are the internal methods not called. — GuidoG, Jan 29 '21 at 12:27
@OlivierRogier The first link in your comment, look at the author of that quetion. It was me. I abandonend that because another SO user informed it would not work like that. The only solution was to serialize the columns to another collection (hence the collection in my question) and then use them after deserializing. My problem is the deserializing methods are not called — GuidoG, Jan 29 '21 at 12:30
Downvoters please let me know where I can improve this question — GuidoG, Jan 29 '21 at 12:31
@GuidoG No need to be public. I got this code working with `var obj = (gttDataTable)new BinaryFormatter().Deserialize(File.Open("d:\\DataFile.dat", FileMode.Open));`. OnDeserializing and OnDeserialized are called as expected. You need to add more details and code. Just a note, I wanted to write it in my previous comment but forgot: `[Serializable] public class ConfigColumn`. — , Jan 29 '21 at 12:41
@OlivierRogier I do not want to serialize/deserialize to an external file. I need this done in the Designer.cs from VS. What more details do you want, this is the entire code, there is nothing more. The question is actuall simple, I want custom serialization in Designer.cs, I followed the documentation, but the methods are not called. Why are they not called — GuidoG, Jan 29 '21 at 13:15

Rekshino · Accepted Answer · 2021-01-29T13:15:57.813

1

Not all serializer take into consideration such attribute as OnDeserializing etc. see e.g. Why does the OnDeserialization not fire for XML Deserialization?.
If I'm not mistaken designer does use CodeDomSerializer.

To make custom serailization you need to derive from CodeDomSerializer and decorate the class with DesignerSerializerAttribute

[DesignerSerializerAttribute(typeof(YourCustomSerializer), typeof(CodeDomSerializer))]
public partial class gttDataTable : Component
{
}

edited Jan 29 '21 at 13:15

answered Jan 29 '21 at 13:01

Rekshino

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what should I use for YourCustomSerializer ? – GuidoG Jan 29 '21 at 13:16
See the link for CodeDomSerializer there is an example. – Rekshino Jan 29 '21 at 13:17
OK I will try this and update when I have results – GuidoG Jan 29 '21 at 13:19
I tried it and it seems to have some effect with serialization. I still have to research it more since I now get strange serialization errors like "cannot convert "gttControls.ConfigColumn" to "gttControls.ConfigColumn". But at least I am getting something from the serialization/deserialization now. – GuidoG Jan 29 '21 at 15:10
Yes I got it working with the CodeDomSerializer. Thank you so much – GuidoG Jan 29 '21 at 15:29

how to execute code after deserializing a custom component?

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