ExMessage

This structure is used to hold message and is defined as follows:

struct ExMessage
{
	USHORT message;					// The message identifier.
	union
	{
		// Data of the mouse message
		struct
		{
			bool ctrl		:1;		// Indicates whether the CTRL key is down.
			bool shift		:1;		// Indicates whether the SHIFT key is down.
			bool lbutton	:1;		// Indicates whether the left mouse button is down.
			bool mbutton	:1;		// Indicates whether the middle mouse button is down.
			bool rbutton	:1;		// Indicates whether the right mouse button is down.
			short x;				// The x-coordinate of the cursor.
			short y;				// The y-coordinate of the cursor.
			short wheel;			// The distance the wheel is rotated, expressed in multiples or divisions of 120.
		};

		// Data of the key message
		struct
		{
			BYTE vkcode;			// The virtual-key code of the key.
			BYTE scancode;			// The scan code of the key. The value depends on the OEM.
			bool extended	:1;		// Indicates whether the key is an extended key.
			bool prevdown	:1;		// Indicates whether the key is previously up or down.
		};

		// Data of the char message
		TCHAR ch;

		// Data of the window message
		struct
		{
			WPARAM wParam;
			LPARAM lParam;
		};
	};
};

Members

message

Specify the message identifier, which can be the following values.

ctrl

Indicates whether the Ctrl key is pressed. It is valid only when the message category is EX_MOUSE.

shift

Indicates whether the SHIFT key is pressed. It is valid only when the message category is EX_MOUSE.

lbutton

Indicates whether the left mouse button is pressed. It is valid only when the message category is EX_MOUSE.

mbutton

Indicates whether the middle mouse button is pressed. It is valid only when the message category is EX_MOUSE.

rbutton

Indicates whether the right mouse button is pressed. It is valid only when the message category is EX_MOUSE.

x

The x-coordinate of the cursor (physical coordinates). It is valid only when the message category is EX_MOUSE.

y

The y-coordinate of the cursor (physical coordinates). It is valid only when the message category is EX_MOUSE.

wheel

The mouse wheel scroll value, a multiple of 120. It is valid only when the message category is EX_MOUSE.

vkcode

The virtual-key code of the key. It is valid only when the message category is EX_KEY.

All virtual-key codes are listed on the Microsoft website: https://docs.microsoft.com/windows/win32/inputdev/virtual-key-codes

scancode

The scan code of the key. The value depends on the OEM. It is valid only when the message category is EX_KEY.

extended

Indicates whether the key is an extended key, such as a function key or a key on the numeric keypad. It is valid only when the message category is EX_KEY.

prevdown

Indicates whether the key is previously up or down. It is valid only when the message category is EX_KEY.

ch

The character received. It is valid only when the message category is EX_CHAR.

wParam

The wParam parameter corresponding to the message. It is valid only when the message category is EX_WINDOW.

lParam

The lParam parameter corresponding to the message. It is valid only when the message category is EX_WINDOW.

Examples

None