C# serialize generic list to file

Question

i got a class which holds info about pictures, like filepath, hashvalue, bytes. in another class i got a generic list where i put objects from the class that holds picture info.

that class looks like this:

[Serializable()]
    class PicInfo : ISerializable
    {
        public string fileName { get; set; }
        public string completeFileName { get; set; }
        public string filePath { get; set; }
        public byte[] hashValue { get; set; }

        public PicInfo()
        { }

        public PicInfo(SerializationInfo info, StreamingContext ctxt)
        {
            this.fileName = (string)info.GetValue("fileName", typeof(string));
            this.completeFileName = (string)info.GetValue("completeFileName", typeof(string));
            this.filePath = (string)info.GetValue("filePath", typeof(string));
            this.hashValue = (byte[])info.GetValue("hashValue", typeof(byte[]));
        }

        public void GetObjectData(SerializationInfo info, StreamingContext ctxt)
        {
            info.AddValue("fileName", this.fileName);
            info.AddValue("completeFileName", this.completeFileName);
            info.AddValue("filePath", this.filePath);
            info.AddValue("hashValue", this.hashValue);
        }
    }

my list is just list<picinfo> pi = new list<picinfo>(); what would be the eaziest way to serialize this list?

Answer 1

If you want to use BinaryFormatter (which I really don't advise), you can use:

[Serializable]
class PicInfo
{
    public string fileName { get; set; }
    public string completeFileName { get; set; }
    public string filePath { get; set; }
    public byte[] hashValue { get; set; }

    public PicInfo()  { }
}
static class Program
{
    static void Main()
    {
        List<PicInfo> pi = new List<PicInfo>();
        pi.Add(new PicInfo {fileName = "foo.bar", hashValue = new byte[] {1, 2, 3}});

        var ser = new BinaryFormatter();
        using (var ms = new MemoryStream())
        {
            ser.Serialize(ms, pi);
            var bytes = ms.ToArray();
        }
    }
}

If you want to use XmlSerializer (probably preferable IMO), but need the byte[], then:

public class PicInfo
{
    public string fileName { get; set; }
    public string completeFileName { get; set; }
    public string filePath { get; set; }
    public byte[] hashValue { get; set; }

    public PicInfo()  { }
}
static class Program
{
    static void Main()
    {
        List<PicInfo> pi = new List<PicInfo>();
        pi.Add(new PicInfo {fileName = "foo.bar", hashValue = new byte[] {1, 2, 3}});

        var ser = new XmlSerializer(typeof(List<PicInfo>));
        using (var ms = new MemoryStream())
        {
            ser.Serialize(ms, pi);
            var bytes = ms.ToArray();
        }
    }
}

Personally, I'd use protobuf-net:

[ProtoContract]
public class PicInfo
{
    [ProtoMember(1)]public string fileName { get; set; }
    [ProtoMember(2)]public string completeFileName { get; set; }
    [ProtoMember(3)]public string filePath { get; set; }
    [ProtoMember(4)]public byte[] hashValue { get; set; }

    public PicInfo()  { }
}
static class Program
{
    static void Main()
    {
        List<PicInfo> pi = new List<PicInfo>();
        pi.Add(new PicInfo {fileName = "foo.bar", hashValue = new byte[] {1, 2, 3}});

        using (var ms = new MemoryStream())
        {
            Serializer.Serialize(ms, pi);
            var bytes = ms.ToArray();
        }
    }
}

Sizes:

• BinaryFormatter: 488 bytes
• XmlSerializer: 251 bytes
• protobuf-net: 16 bytes