page no.64


key and then releasing the shift key,the window proceduer receives five message
message key or code.
WM_KEYDOWN     virtual key code VK_SHIFT(0x10)
VM_KEYDOWN      virtual key code 'A' (0x41)
WM_CHAR              character code for 'A' (0x41)
WM_KEYUP            virtual key code for 'A' (0x41)
WM_KEYUP            virtual key code VK_SHIFT (0x10)

the shift key by itself does not generate a character message if we hold down the A key so that the typematic action generates keystroke,we will get a character message for each  WM_KEYDOWN message.

message key or code
WM_KEYDOWN      virtual key code for 'A' (0x41)
WM_CHAR                character code for 'a' (0x61)
WM_KEYDOWN      virtual key code for 'A' (0x41)
WM_CHAR                character key code for 'a' (0x61)
WM_KEYDOWN      virtual key code for 'A' (0x41)
WM_CHAR                character key code for 'a' (0x61)
WM_KEYDOWN      virtual key code for 'A' (0x41)
WM_CHAR                character key code for 'a' (0x61)
WM_KEYUP              virtual key code for 'A' (0x41)