拖动div简单事例代码

事例文件下载

//拖动容器代码 
var rDrag = {
    o: null,
    init: function (o) {
        o.onmousedown = this.start;
    },
    start: function (e) {
        var o;
        e = rDrag.fixEvent(e);
        e.preventDefault && e.preventDefault();
        rDrag.o = o = this;
        o.x = e.clientX - rDrag.o.offsetLeft;
        o.y = e.clientY - rDrag.o.offsetTop;
        document.onmousemove = rDrag.move;
        document.onmouseup = rDrag.end;
    },
    move: function (e) {
        e = rDrag.fixEvent(e);
        var oLeft, oTop;
        oLeft = e.clientX - rDrag.o.x;
        oTop = e.clientY - rDrag.o.y;
        rDrag.o.style.left = oLeft + 'px';
        rDrag.o.style.top = oTop + 'px';
    },
    end: function (e) {
        e = rDrag.fixEvent(e);
        rDrag.o = document.onmousemove = document.onmouseup = null;
    },
    fixEvent: function (e) {
        if (!e) {
            e = window.event;
            e.target = e.srcElement;
            e.layerX = e.offsetX;
            e.layerY = e.offsetY;
        }
        return e;
    }
}

//调用代码
 window.onload=function() {
 var obj = document.getElementById('demo');
        rDrag.init(obj);
 };


html代码
<div id="demo"  style="width: 100px; height: 100px; position: absolute;">拖动我</div>

拖动我