C# : Converting Base Class to Child Class

As long as the object is actually a SkyfilterClient, then a cast should work. Here is a contrived example to prove this:

using System;

class Program
{
    static void Main()
    {
        NetworkClient net = new SkyfilterClient();
        var sky = (SkyfilterClient)net;
    }
}

public class NetworkClient{}
public class SkyfilterClient : NetworkClient{}

However, if it is actually a NetworkClient, then you cannot magically make it become the subclass. Here is an example of that:

using System;

class Program
{
    static void Main()
    {
        NetworkClient net = new NetworkClient();
        var sky = (SkyfilterClient)net;
    }
}

public class NetworkClient{}
public class SkyfilterClient : NetworkClient{}

HOWEVER, you could create a converter class. Here is an example of that, also:

using System;

class Program
{
    static void Main()
    {
        NetworkClient net = new NetworkClient();
        var sky = SkyFilterClient.CopyToSkyfilterClient(net);
    }
}

public class NetworkClient
{  
  public int SomeVal {get;set;}
}

public class SkyfilterClient : NetworkClient
{
    public int NewSomeVal {get;set;}
    public static SkyfilterClient CopyToSkyfilterClient(NetworkClient networkClient)
    {
        return new SkyfilterClient{NewSomeVal = networkClient.SomeVal};
    }
}

But, keep in mind that there is a reason you cannot convert this way. You may be missing key information that the subclass needs.

Finally, if you just want to see if the attempted cast will work, then you can use is:

if(client is SkyfilterClient)
    cast

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