The WM_MDITILE message is sent to a multiple document interface (MDI) client window to arrange all its child windows in a tiled format.
wParam
Specifies a tiling flag. This parameter can be one of the following flags:
| Value | Meaning |
| MDITILE_HORIZONTAL | Tiles MDI child windows vertically (one window appears above another). |
| MDITILE_SKIPDISABLED | Prevents disabled MDI child windows from being tiled. |
| MDITILE_VERTICAL | Tiles MDI child windows horizontally (one window appears beside another). |
lParam
This parameter is not used.