Sometimes, though, you want an object to capture events that occur within other objects. You can do it with the setCapture() method:

object.setCapture([flag]);

where flag is an optional parameter equal to either false (no capturing), or true (default).

The following box is designed to capture onmousemove events from the whole document. You can turn this capturing off and on by a mouse click. Play around with the mouse and make sure the setCapture() method is working according to the specifications.

Supported mouse events include onmousedown, onmouseup, onmousemove, onclick, ondblclick, onmouseover, and onmouseout. The srcElement property of the window's event object always returns the object that is positioned under the mouse rather than the object that has mouse capture. The following key events are unaffected by mouse capture, and fire as usual: onkeydown, onkeyup, and onkeypress.

For more on the event model, go to Column 9, The Navigator Event Model, Column 10, The Internet Explorer Event Model, and Column 11, The Cross Browser Event Model.

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