Question

I have the following problem. I have an array of bytes that I want to convert intro an array of primitive types. But I don’t know the type. (This is given as an array of types). As a result I need an array of objects.

Of course I could use a switch on the types (there are only a limited number of them), but I wonder if there is a better solution for that.

Example:

byte[] byteData = new byte[] {0xa0,0x14,0x72,0xbf,0x72,0x3c,0x21}
Type[] types = new Type[] {typeof(int),typeof(short),typeof(sbyte)};

//some algorithm

object[] primitiveData = {...};
//this array contains an the following elements
//an int converted from 0xa0,0x14,0x72,0xbf
//a short converted from 0x72, 0x3c
//a sbyte converted from 0x21

Is there an algorithm for this or should I use a switch

Answer 1

This code uses unsafe to get a pointer to the byte array buffer, but that shouldn’t be a problem.

[Edit – changed code after comment]

byte[] byteData = new byte[] { 0xa0, 0x14, 0x72, 0xbf, 0x72, 0x3c, 0x21 };
Type[] types = new Type[] { typeof(int), typeof(short), typeof(sbyte) };

object[] result = new object[types.Length];
unsafe
{
    fixed (byte* p = byteData)
    {
        var localPtr = p;
        for (int i = 0; i < types.Length; i++)
        {
            result[i] = Marshal.PtrToStructure((IntPtr)localPtr, types[i]);
            localPtr += Marshal.SizeOf(types[i]);
        }
    }
}