#div1 {

		width: 100px;

		height: 100px;

		background: red;

		position: absolute;

	}

<div id="div1">

	</div>

     window.onload = function () {

         var oDiv = document.getElementById('div1');

         //pc端

         oDiv.onmousedown = function (ev) {

             var oEvent = ev || event; //需要获取和事件相关的信息时使用

             var disX = oEvent.clientX - oDiv.offsetLeft;

             var disY = oEvent.clientY - oDiv.offsetTop;

             document.onmousemove = function (ev) {

                 var oEvent = ev || event;

                 var l = oEvent.clientX - disX;

                 var t = oEvent.clientY - disY;

                 if (l < 0) {

                     l = 0;

                 } else if (l > document.documentElement.clientWidth - oDiv.offsetWidth) {

                     l = document.documentElement.clientWidth - oDiv.offsetWidth;

                 }

                 if (t < 0) {

                     t = 0;

                 } else if (t > document.documentElement.clientHeight - oDiv.offsetHeight) {

                     t = document.documentElement.clientHeight - oDiv.offsetHeight;

                 }

                 oDiv.style.left = l + 'px';

                 oDiv.style.top = t + 'px';

             };

             document.onmouseup = function () {

                 document.onmousemove = null;

                 document.onmouseup = null;

             };

         };

         //移动端

         // 拖拽

         // 获取节点

         var block = document.getElementById("right");

         var oW, oH;

         // 绑定touchstart事件

         oDiv.addEventListener("touchstart", function (e) {

             var touches = e.touches[0];

             oW = touches.clientX - oDiv.offsetLeft;

             oH = touches.clientY - oDiv.offsetTop;

             //阻止页面的滑动默认事件

             document.addEventListener("touchmove", defaultEvent, false);

         }, false);

         oDiv.addEventListener("touchmove", function (e) {

             var touches = e.touches[0];

             var oLeft = touches.clientX - oW;

             var oTop = touches.clientY - oH;

             if (oLeft < 0) {

                 oLeft = 0;

             } else if (oLeft > document.documentElement.clientWidth - oDiv.offsetWidth) {

                 oLeft = (document.documentElement.clientWidth - oDiv.offsetWidth);

             }

             oDiv.style.left = oLeft + "px";

             oDiv.style.top = oTop + "px";

         }, false);

         oDiv.addEventListener("touchend", function () {

             document.removeEventListener("touchmove", defaultEvent, false);

         }, false);

         function defaultEvent(e) {

             e.preventDefault();

         };

     };