what is the ascii value for (alt key , flag key, ctrl key)?

Answer 1

There is none, they are modifiers.

CTRL is usually signalled by mapping an alphabetic key to its position - that is, ^A = 1, ...^Z = 26.

Some programs used to use bit 7 (the sign bit) to signal alt, but that is frowned on because it only works for basic ASCII, and is not extensible to other character sets.

If you are writing a program using these you need to pass (or read) a separate modifier flag to find if these are set.

Answer 2

From MS:
The WM_KEYDOWN message is posted to the window with the keyboard focus when a nonsystem key is pressed. A nonsystem key is a key that is pressed when the ALT key is not pressed.

A window receives this message through its WindowProc function.

LRESULT CALLBACK WindowProc(
HWND hwnd, // handle to window
UINT uMsg, // WM_KEYDOWN
WPARAM wParam, // virtual-key code
LPARAM lParam // key data

The info about the key is found in the virtual keycode and key data. You can look this up in various MS documentation and you'll see that you can get the actual key pressed along with whether ctrl or alt is simultaneously pressed. As the other answers have said, those keys are modifiers.

Answer 3

because of the fact if attempt to make a capital O, you're meant to press the shift key on the left with your left hand, and the O with your appropriate hand. in case you had to make a capital W, you're technically meant to apply the marvelous shift key, yet I in no way do. I consistently use the left shift key. same is going for ctrl and alt.

Answer 4

ASCII is a character encoding of the various inputs to PC. These keys do not have a ASCII value.

Answer 5

They're considered modifiers and do not have ASCII values.