How to convert Struct Array to Byte Array in c#?

Question

It is easy to convert primitive types to bytes by using Buffer.BlockCopy().

But if I have a array of DateTime, which function should I use to convert the DateTime[] to byte[]?

If I have a constant size of struct (which means I can use Marshal to convert struct to byte[]), which way should I use to convert the T[](struct array) to byte[]?

Answer 1

If you are after a copy of the underlying in-memory representation, then one approach is to just access the data unsafe - something like:

// invent some data
DateTime[] original = new DateTime[10];
for (int i = 0; i < original.Length; i++)
    original[i] = new DateTime(2014, 1, i + 1);

byte[] blob = new byte[original.Length * sizeof(DateTime)];

fixed (DateTime* src = original)
fixed (byte* dest = blob)
{
    DateTime* typedDest = (DateTime*)dest;
    for(int i = 0; i < original.Length; i++)
    {
        typedDest[i] = src[i];
    }
} 

However, this is hugely dependent upon what you expect the contents of the byte[] to be afterwards, and what you intend doing with it.