I am trying to build a class and I keep getting a 'cannot derive from sealed class' error. The class is actually a struct. If I copy it, I still get the same error...: class, derive, from, sealed

I am trying to build a class and I keep getting a 'cannot derive from sealed class' error. The class is actually a struct. If I copy it, I still get the same error...

Hello all you experts. Boy, do I need your help. I'm trying to convert a java project to .net and I'm having one problem that is killing me. It concerns the DictionaryEntry struct. No matter what I do, I cannot inherit from it. Now, I understand why (because M$ seals freaking everything!), but I don't understand why, if I copy the DictionaryEntry struct into my file, and then use this struct instead, I'm still getting the same error. I don't know if it's because it's a struct and not an actual class...I mean, as you can see from the code of the DictionaryEntry class/struct, there are only two properties and no methods per se--so I can't add virtual to any of the properties, right?

public struct DictionaryEntry
{
      // Instance fields.
      private Object key_;
      private Object value_;

      // Construct a dictionary entry.
      public DictionaryEntry(Object key, Object value)
      {
            if(key == null)
            {
                  throw new ArgumentNullException("key");
            }
            key_ = key;
            value_ = value;
      }

      // DictionaryEntry properties.
      public Object Key
      {
            get
            {
                  return key_;
            }
            set
            {
                  if(value == null)
                  {
                        throw new ArgumentNullException("value");
                  }
                  key_ = value;
            }
      }
      public Object Value
      {
            get
            {
                  return value_;
            }
            set
            {
                  value_ = value;
            }
      }

My question is, how do I change the above code so I can derive classes from the DictionaryEntry class?

This is obviously a question that only CSharp experts (compared to me anyway!) would know, so I'm offering 500 points to the expert who can print the above code with the changes so I can subclass it...Thanks so much for your help!

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I am trying to build a class and I keep getting a 'cannot derive from sealed class' error. The class is actually a struct. If I copy it, I still get the same error...

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C# Programming Language

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