design problem (binary parser)

I've seen this problem before.

You could make use of the provider pattern here. You would have an instance of a class that creates different objects and serves them to the caller, based on a type id (in this case the two bytes from your binary stream). That same provider can also contain the logic for parsing the rest of the binary value and place the result in the created object.

JonathanvandeVeen at 2007-9-4 >

In the inherited BinaryParser, I added a method for each concrete type to read:
public ContentInteger ReadContentInteger();
public ContentString ReadContentString();

public ContentListString ReadContentListString();
etc.

The thing that looks dirty with this solution is for the astract class:
public Content ReadContent()
{
ContentType id = (ContentType)ReadInt16();
BaseStream.Seek(StreamPosition.Current, -2);
switch (id)
{
case ContentType.Integer:
return ReadContentInteger();
case ContentType.String:

return ReadContentString();

case ContentType.ListString:

return ReadContentListString();

[...]
}
}

but as a temporary solution I guess it could do (even if it's ugly)

Nerick at 2007-9-4 >