1             // 获取节点 2             var block = document.getElementById("right"); 3             var oW, oH; 4             // 绑定touchstart事件 5             block.addEventListener("touchstart", function (e) { 6                 var touches = e.touches[0]; 7                 oW = touches.clientX - block.offsetLeft; 8                 oH = touches.clientY - block.offsetTop; 9                 //阻止页面的滑动默认事件10                 document.addEventListener("touchmove", defaultEvent(event), false);11             }, false);12             block.addEventListener("touchmove", function (e) {13                 var touches = e.touches[0];14                 var oLeft = touches.clientX - oW;15                 var oTop = touches.clientY - oH;16                 if (oLeft < 0) {17                     oLeft = 0;18                 } else if (oLeft > document.documentElement.clientWidth - block.offsetWidth) {19                     oLeft = (document.documentElement.clientWidth - block.offsetWidth);20                 }21                 block.style.left = oLeft + "px";22                 block.style.top = oTop + "px";23             }, false);24             block.addEventListener("touchend", function () {25                 document.removeEventListener("touchmove", defaultEvent(event), false);26             }, false);27             function defaultEvent(event) {28                 event.preventDefault();29             };