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c#binarymanageddeserialization

Deserializing a byte array


If I wanted to fill a structure from a binary file, I would use something like this:

using (BinaryReader br = new BinaryReader(File.Open(filename, FileMode.Open)))
{
    myStruct.ID = br.ReadSingle();
    myStruct.name = br.ReadBytes(20);
}

However, I must read the whole file into a byte array before deserializing, because I want to do some pre-processing. Is there any managed way to fill my structure from the byte array, preferably similar to the one above?


Solution

  • This is a sample to take some data (actually a System.Data.DataSet) and serialize to an array of bytes, while compressing using DeflateStream.

    try
    {
        var formatter = new BinaryFormatter();
        byte[] content;
        using (var ms = new MemoryStream())
        {
             using (var ds = new DeflateStream(ms, CompressionMode.Compress, true))
             {
                 formatter.Serialize(ds, set);
             }
             ms.Position = 0;
             content = ms.GetBuffer();
             contentAsString = BytesToString(content);
         }
    }
    catch (Exception ex) { /* handle exception omitted */ }
    

    Here is the code in reverse to deserialize:

            var set = new DataSet();
            try
            {
                var content = StringToBytes(s);
                var formatter = new BinaryFormatter();
                using (var ms = new MemoryStream(content))
                {
                    using (var ds = new DeflateStream(ms, CompressionMode.Decompress, true))
                    {
                        set = (DataSet)formatter.Deserialize(ds);                        
                    }
                }
            }
            catch (Exception ex)
            {
                // removed error handling logic!
            }
    

    Hope this helps. As Nate implied, we are using MemoryStream here.