function addEvent( obj, type, fn ) {
if ( obj.attachEvent )
{
obj['e'+type+fn] = fn;
obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
obj.attachEvent( 'on'+type, obj[type+fn] );
}
else
{
obj.addEventListener( type, fn, false );
}
}
function removeEvent( obj, type, fn )
{
if ( obj.detachEvent )
{
obj.detachEvent( 'on'+type, obj[type+fn] );
obj[type+fn] = null;
}
else
{
obj.removeEventListener( type, fn, false );
}
}