最近需要项目需要实现弹幕，网上参考了各种方法，最后觉得transform+transition实现的效果在移动设备上性能最好，在iphone6和红米4上测试，看不到卡顿的感觉。用jquery的animate动画在移动设备上有明显的卡顿。
1.首先创建弹幕区域
<div class="barrage"><div class="mask"><!--//弹幕内容--></div></div><input type="text" ng-model="data.comment"/><button ng-click="addDanmu()">说两句</button >
2.css
.webPage .barrage{width:100%;height:22%;position: absolute; bottom: 50px; background-color: transparent;pointer-events: none;}.webPage .barrage .mask{width:100%;height:100%;background:transparent;z-index:100;}注：以上html,css根据自己需求来即可
3.js
$scope.data = {comment:""};$scope.danmuCount = 5; //最大弹幕行数$scope.danmus = ["1545466666还是","9777777","哈哈哈哈哈","对企业读完后环球网好齐齐哈","42115我我我5","556噢噢噢噢45","54哦","54545646","666但近段时间66","56565","454465465565", "1545466666还是","9777777","哈哈哈哈哈","对企业读完后环球网好齐齐哈","42115我我我5","556噢噢噢噢45","54哦","54545646","666但近段时间66","56565","454465465565"]; //弹幕数据源//创建弹幕区域$scope.createDanmuContent = function () {var height = 1 / $scope.danmuCount * 100 + "%";for (var i = 0; i < $scope.danmuCount; i++) {var item = "<div style="width: 100%; height: "+height+""></div>";$(".mask").append(item);} $scope.createDanmu ();};//开始弹幕绘制$scope.createDanmu = function () {var maxCount = 0;if ($scope.danmus.length > $scope.danmuCount) { maxCount = $scope.danmuCount; } else {maxCount = $scope.danmus.length;}var _left = window.screen.width;for (var i = 0; i < maxCount; i++) {var _lable = $("<p style="margin: 0;position: absolute;opacity:1;display:table;left: "+_left + "px"+";color:"+$scope.getRandomColor()+"">"+$scope.danmus[i]+"</p>");$(".mask div").each(function () {//检测该区域是否绘制了弹幕if ($scope.checkDanmu($(this))) {$(this).append(_lable);$scope.moveArray(i); i--;return false;}});}$scope.init_barrage();};//将数组第一位放到最后一位,（因弹幕池内容太少，所以没删除已显示的弹幕）$scope.moveArray = function (i) { var temp = $scope.danmus[i];$scope.danmus.splice(i,1);$scope.danmus.push(temp);}//判断content区域有没有弹幕$scope.checkDanmu = function (el) {return el.find("p").length == 0 ? true : false;};//获取随机颜色$scope.getRandomColor = function () {return "#" + (function(h){return new Array(7 - h.length).join("0") + h})((Math.random() * 0x1000000 << 0).toString(16))};//初始化弹幕参数$scope.init_barrage = function () {$(".mask div p").show().each(function() { var _moveLeft = window.screen.width+$(this).width();var time = 100000 / $(this).width() + 5000;//弹幕滑动时间$scope.addCssAnimate($(this),_moveLeft,time);});};//添加弹幕动画$scope.addCssAnimate = function (el,_moveLeft,time) {el.css({"transform":"translateX("+-_moveLeft+"px)","transition":"all "+time+"ms"+ " linear","-webkit-transform":"translateX("+-_moveLeft+"px)","-webkit-transition":"all "+time+"ms"+ " linear","-moz-transform":"translateX("+-_moveLeft+"px)","-moz-transition":"all "+time+"ms"+ " linear","-ms-transform":"translateX("+-_moveLeft+"px)","-ms-transition":"all "+time+"ms"+ " linear"});//当动画执行完毕后，将弹幕移到原处，更换弹幕文字，重新开始执行动画，相当于对原本弹幕的复用$timeout(function () {//判断弹幕池是否还有内容，如果没有则移除弹幕if ($scope.danmus.length > 0) {el.css({"transform":"translateX(0px)","transition":"all 0ms linear","-webkit-transform":"translateX(0px)","-webkit-transition":"all 0ms linear","-moz-transform":"translateX(0px)","-moz-transition":"all 0ms linear","-ms-transform":"translateX(0px)","-ms-transition":"all 0ms linear"});$scope.resetAnimate(el);} else {el.remove();}},time);};//更换弹幕内容，重新开始弹幕动画$scope.resetAnimate = function (el) {el.html($scope.danmus[0]);$scope.moveArray(0);var _moveLeft = el.width() + screen.width;var time = 100000 / el.width() + 5000;$scope.addCssAnimate(el,_moveLeft,time);};//评论，添加弹幕$scope.addDanmu = function () {var text = $scope.data.comment;if(text == ""){return;}$scope.danmus.unshift(text);};$scope.createDanmuContent();至此，功能基本实现了。要关闭弹幕只需移除弹幕的区域，文中就没有写了。
逻辑：首先根据$scope.danmuCount来创建弹幕的行数，然后在每行里面添加弹幕，并添加相应的动画。当一个动画执行完毕后，将弹幕移回原处，更换弹幕内容，重新执行动画，这样避免了弹幕重叠。每条弹幕动画执行时间是根据弹幕长度决定的。
个人经验，希望大家指出不足。上述代码使用的angularjs，但逻辑都是一样
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持网页设计。
