var mydrag={
mousePoint: {x:0,y:0}, //初始化坐标
drag: function(){
var that=this; //保存当前对象即(mydrag)，如果不保存，在mousedown()里访问不了mydrag这个对象
var targetid=$(".dragtitle");
targetid.mousedown(function(event){
var e=event;
var offsetLeft=targetid.offset().left; //当前div的左偏移距离
var offsetTop=targetid.offset().top; //当前div的顶部偏移距离
that.mousePoint.x=e.clientX-offsetLeft;//计算鼠标点击时离它自己div的横向距离
that.mousePoint.y=e.clientY-offsetTop; //计算鼠标点击时离它自己div的纵向距离
$(document).bind('mousemove',move);
e.stopPropagation();
});
function move(event){
var e =event;
var Left=e.clientX-that.mousePoint.x; //移动后，重新计算左偏移和顶部偏移距离
var Top=e.clientY-that.mousePoint.y;
$("#drag").css({'top':Top,'left':Left,'margin':0});
$(document).bind('mouseup',end);
e.stopPropagation();
};
function end(event){
var e = event;
$(document).unbind('mousemove', move);
$(document).unbind('mouseup',end);
e.stopPropagation();
};
}
}
mydrag.drag();
