Read-only array field in unsafe struct

foreach (FieldInfo fi in typeof(MyStruct).GetFields(BindingFlags.Public | BindingFlags.Instance))
{
    var attr = fi.GetCustomAttributes(typeof(FixedBufferAttribute), false);
    if(attr.Length > 0)
        output += fi.Name + ": " + ((FixedBufferAttribute)attr[0]).ElementType + "\r\n";
    else
        output += fi.Name + ": " + fi.FieldType + "\r\n";
}

var type = typeof (MyStruct)
            .GetField("Field2")
            .GetCustomAttributes(typeof (FixedBufferAttribute), false)
            .Cast<FixedBufferAttribute>()
            .Single()
            .ElementType;

[StructLayout(LayoutKind.Sequential, Pack=1)]
public struct MyStruct
{
    public uint Field1;
    [FixedBuffer(typeof(sbyte), 10)]
    public <Field2>e__FixedBuffer0 Field2;
    public ulong Field3;
    // Nested Types
    [StructLayout(LayoutKind.Sequential, Size=10), CompilerGenerated, UnsafeValueType]
    public struct <Field2>e__FixedBuffer0
    {
       public sbyte FixedElementField;
    }
}

for (int i = 0; i < 3; i++)
{
    dynamicState.AngularVelocity[i] = array[i];
}

Marshal.Copy(array, 0, new IntPtr(dynamicState.AngularVelocity), array.Length);

public static double[] CopyFixedDoubleArray(this Data data)
{
    unsafe
    {
        return new[] { data.Values[0], data.Values[1], data.Values[2] };
    }
}