使用js实现的简单拖拽效果(2)

<style>
        * {
            margin:0;
            padding:0;
        }
        #div1 {
            width: 100px;
            height: 100px;
            background-color: red;
        }
        #div2 {
            background-color:yellow;
            width:100px;
            height:100px;
        }
    </style>
<div></div>
<div></div>

js Draggle class:

复制代码 代码如下:

 function Drag(id) {
            this.div = document.getElementById(id);
            if (this.div) {
                this.div.style.cursor = "move";
                this.div.style.position = "absolute";
            }
            this.disX = 0;
            this.disY = 0;
            var _this = this;
            this.div.onmousedown = function (evt) {
                _this.getDistance(evt);
                document.onmousemove = function (evt) {
                    _this.setPosition(evt);
                }
                _this.div.onmouseup = function () {
                    _this.clearEvent();
                }
            }
        }
        Drag.prototype.getDistance = function (evt) {
            var oEvent = evt || event;
            this.disX = oEvent.clientX - this.div.offsetLeft;
            this.disY = oEvent.clientY - this.div.offsetTop;
        }
        Drag.prototype.setPosition = function (evt) {
            var oEvent = evt || event;
            var l = oEvent.clientX - this.disX;
            var t = oEvent.clientY - this.disY;
            if (l <= 0) {
                l = 0;
            }
            else if (l >= document.documentElement.clientWidth - this.div.offsetWidth) {
                l = document.documentElement.clientWidth - this.div.offsetWidth;
            }
            if (t <= 0) {
                t = 0;
            }
            else if (t >= document.documentElement.clientHeight - this.div.offsetHeight) {
                t = document.documentElement.clientHeight - this.div.offsetHeight;
            }
            this.div.style.left = l + "px";
            this.div.style.top = t + "px";
        }
        Drag.prototype.clearEvent = function () {
            this.div.onmouseup = null;
            document.onmousemove = null;
        }

at last：最终实现：

复制代码 代码如下: