HITTEST 字段

In the border of a window that does not have a sizing border.

In the lower-horizontal border of a resizable window (the user can click the mouse to resize the window vertically).

In the lower-left corner of a border of a resizable window (the user can click the mouse to resize the window diagonally).

In the lower-right corner of a border of a resizable window (the user can click the mouse to resize the window diagonally).

In a title bar.

In a client area.

In a Close button.

On the screen background or on a dividing line between windows (same as HTNOWHERE; except that the DefWindowProc function produces a system beep to indicate an error).

In a size box (same as HTSIZE).

In a Help button.

In a horizontal scroll bar.

In the left border of a resizable window (the user can click the mouse to resize the window horizontally).

In a Maximize button.

In a menu.

In a Minimize button.

On the screen background or on a dividing line between windows.

In the right border of a resizable window (the user can click the mouse to resize the window horizontally).

In a window menu or in a Close button in a child window.

In the upper-horizontal border of a window.

In the upper-left corner of a window border.

In the upper-right corner of a window border.

In a window currently covered by another window in the same thread (the message will be sent to underlying windows in the same thread until one of them returns a code that is not HTTRANSPARENT).

In the vertical scroll bar.