The following table shows the four possible responses available to the target when it receives a DM_DRAGOVER message. The target sends these values to the window handle specified in the DRAGINFO data structure.
旼컴컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 쿘essage Name 쿏escription � 쳐컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 쿏OR_DROP 쿞ent if the objects being dragged are � � 쿪cceptable. A drop does not occur unless� � 쿏OR_DROP is returned. � 쳐컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 쿏OR_NODROP 쿞ent if the objects being dragged are � � 쿪cceptable and the target supports the � � 쿬urrent operation, but the objects � � 쿬annot be dropped on the current � � 쿹ocation in the target window. For � � 쿮xample, a list box might return � � 쿏OR_NODROP if it contains objects that � � 쿬an be dropped on, but the pointer is � � 쿽ver an object that cannot be dropped � � 쿽n. � � 쿔f the target response is DOR_NODROP, � � 퀃he DM_DRAGOVER message continues to be � � 퀂ent to the target when: � � 쿽 The pointer is moved � � 쿽 A keyboard key is pressed � � 쿽 The pointer is moved out of � � � and back into the window. � 쳐컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 쿏OR_NODROPOP 쿞ent if the objects being dragged are � � 쿪cceptable, but the target does not � � 퀂upport the current operation. This � � 퀁esponse implies that the drop may be � � 퀆alid if the drag operation changes. For� � 쿮xample, copying a file to a shredder � � 퀇ould not be valid, but moving a file to� � 쿪 shredder would be. � � 쿚nce the target has sent DOR_NODROPOP, � � 쿻o further DM_DRAGOVER messages is sent � � 퀃o the target until: � � 쿽 A keyboard key is pressed � � 쿽 The pointer is moved out of � � � and back into the window. � 쳐컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 쿏OR_NEVERDROP 쿞ent when the objects being dragged are � � 쿻ot acceptable, and the target will � � 쿻ever accept them. � � 쿚nce the target has sent DOR_NEVERDROP, � � 쿻o further DM_DRAGOVER messages are sent� � 퀃o that target until the pointer is � � 쿺oved out of and back into the target � � 퀇indow. � 읕컴컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
If a reply other than DOR_DROP is received from a target, the augmentation emphasis is automatically changed to indicate that no drop is allowed. This gives the user a visible cue that a drop cannot occur. The emphasis is reverted to drop allowed when a DOR_DROP reply is received from some target.