Keystrokes sending incorrect identifier in Win32 - winapi

Question

So I am working on making a calculator with a GUI for a class project and I am currently working on setting up my input detection so I can filter out what keystokes I want to be included in user input and which I want to exclude. I have been debugging it along the way which has been going smoothly up until about 10 complies ago when the wParam value that gets passed in switched from being a Hex value to being a Dec value. I didn't make any significant changes between when it was sending the code in Hex and now as it sends it in Dec so I can't figure out why it changed, in fact I believe it changed after I finished writing a comment to myself in one of the functions I am filtering the message with so I'm pretty confused as to why it changed. The relevant code is posted below (I can't just undo the changes I made because at some point my IDE closed), if someone could tell me why it changed, how to change it back, and if I'm even filtering keystrokes the correct way that would be much appreciated.
The ShiftPressed variable is stored in the class that is using this WinProc method and is accessible to all of these functions. All the code below was working with the wParam being sent in Hex at one point but after I finished the longer comment in the CheckKeyForOp() method, the wParam started being sent in Dec.
LRESULT CALLBACK EditBoxClass::WinProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
switch( msg )
{
case WM_KEYUP:
if( wParam == VK_SHIFT )
ShiftPressed = FALSE;
return 0;
case WM_KEYDOWN:
if( wParam == VK_SHIFT )
{
ShiftPressed = TRUE;
return 1;
}
else if( CheckKeyForNum( wParam ) )
return 1;
else if( CheckKeyForOp( wParam ) )
return 1;
else
return 0;
...
}
BOOL EditBoxClass::CheckKeyForNum( WPARAM wParam )
{
switch( wParam )
{
case 0x30: case VK_NUMPAD0:
case 0x31: case VK_NUMPAD1:
case 0x32: case VK_NUMPAD2:
case 0x33: case VK_NUMPAD3:
case 0x34: case VK_NUMPAD4:
case 0x35: case VK_NUMPAD5:
case 0x36: case VK_NUMPAD6:
case 0x37: case VK_NUMPAD7:
case 0x38: case VK_NUMPAD8:
case 0x39: case VK_NUMPAD9:
default: return FALSE;
}
}
BOOL EditBoxClass::CheckKeyForOp( WPARAM wParam )
{
switch( wParam )
{
case VK_OEM_2: // For both of these keys, VK_OEM_2: "/ and ?" and VL_OEM_MINUS: "- and _" the
case VK_OEM_MINUS: // regular keystroke can be used in the calculator but the "second version"
if( ShiftPressed == TRUE ) return FALSE; // denoted by holding the shift key during the keystroke, cannot be used; so filter.
case VK_OEM_PLUS: // This key acts in the same way the VK_OEM_MINUS key does, having both "+/=" register under the
// VK code VK_OEM_PLUS, but both are operators used by the calculator so allow both
case VK_ADD: case VK_SUBTRACT:
case VK_MULTIPLY: case VK_DIVIDE:
case VK_DECIMAL: case VK_OEM_PERIOD: return TRUE;
default: return FALSE;
}
}

Answer 1

Messages do not give you hex/decimal, they just give you binary numbers, which you can then interpret as hex/decimal as needed.
The only error I see in this code is that CheckKeyForNum() is not returning TRUE for allowed number keys:
BOOL EditBoxClass::CheckKeyForNum( WPARAM wParam )
{
switch( wParam )
{
case 0x30: case VK_NUMPAD0:
case 0x31: case VK_NUMPAD1:
case 0x32: case VK_NUMPAD2:
case 0x33: case VK_NUMPAD3:
case 0x34: case VK_NUMPAD4:
case 0x35: case VK_NUMPAD5:
case 0x36: case VK_NUMPAD6:
case 0x37: case VK_NUMPAD7:
case 0x38: case VK_NUMPAD8:
case 0x39: case VK_NUMPAD9:
return TRUE; // <-- add this
default: return FALSE;
}
}