I'm looking into using raw input on windows for keyboard/mouse detection and I see there are const values for keys such as VK_SHIFT, VK_NUMPAD5, VK_F7 available for me to use but I have no constants for keys like A, S, D, W, 1, etc.

Even on the windows documentation those keys have no associated constant, it only shows the key's HEX value.

So my question is am I missing something like a header file that has these virtual key const defined or is this done on purpose? If it is done on purpose what is the reasoning behind it?

You can just do something like

switch(Keys.IsDown)
{
    case 'W':
    {
      DoStuff();
    } break;
}