波纹按钮实现

摘要：实现原理关键属性画圆放大平滑过渡获取鼠标位置，动态态画圆，延时放大，完成后移除元素部分按钮样式原始波纹样式部分部分合并函数参数工具函数核心点击位置元素位置对象转化为字符串驼峰转连字符添加浏览器兼容前缀获得浏览器前缀

关键属性 border-radius（画圆） transform（scale放大） transition（平滑过渡）
获取鼠标位置，动态态画圆，延时放大，完成后移除元素

按钮样式

</>复制代码 
.btn {
         width: 200px;
         height: 56px;
         line-height: 56px;
         background: #426fc5;
         color: #fff;
         border-radius: 5px;
         text-align: center;
         cursor: pointer;
         overflow: hidden;
       }

原始波纹样式

</>复制代码 
.waves-animation {
       position: absolute;
       border-radius: 50%;
       width: 25px;
       height: 25px;
       background: rgba(255, 255, 255, 0.3);
       transition: all 750ms ease-out;
       transform: scale(0);
   }

</>复制代码 
press me!

</>复制代码 
(function (root, factory, plugName) {
        if (typeof define === "function" && define.amd) {
            define([], factory);
        } else if (typeof module === "object" && module.exports) {
            module.exports = factory();
        } else {
            root[plugName] = factory();
        }
    })(self, function () {
        //合并函数
        var __assign = Object.assign || function (t) {
            for (var s, i = 1, n = arguments.length; i < n; i++) {
                s = arguments[i];
                for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p)) t[p] = s[p];
            }
            return t;
        }
        // 参数
        var __options = {
            selector: ".btn"
        }
        // 工具函数
        var __utils = {
            $: function (selector) {
                return document.querySelector(selector)
            }
        }
        // 核心
        function core(options) {
            this.params = __assign(__options, options)
            this.Element = __utils.$(this.params.selector)
            this.Element.addEventListener("click", this.showWaves.bind(this))
        }
        core.prototype = {
            showWaves: function (e) {
                var insertDiv = document.createElement("div")
                insertDiv.className =insertDiv.className + " waves-animation"
                this.Element.appendChild(insertDiv)
                var _mousePos = this.mousePos(e),
                    _offset = this.offset(this.Element),
                    startCss = {
                        left: _mousePos.x - _offset.left + "px",
                        top: _mousePos.y - _offset.top + "px",
                        opacity: 1
                    },
                    finishCss = {
                        left: _mousePos.x - _offset.left + "px",
                        top: _mousePos.y - _offset.top + "px",
                        opacity: 0
                    }
                startCss[this.prefixStyle("transform")] = "scale(" + _offset.width / 25 + ")"
                finishCss[this.prefixStyle("transform")] = "scale(" + _offset.width / 25 * 2 + ")"
                insertDiv.setAttribute("style", this.getStyle(startCss));
                setTimeout(function () {
                    insertDiv.setAttribute("style", this.getStyle(finishCss));
                    setTimeout(function () {
                        this.Element.removeChild(insertDiv)
                    }.bind(this), 750)
                }.bind(this), 100)
            },
            //点击位置
            mousePos: function (e) {
                return {
                    x: e.pageX,
                    y: e.pageY
                };
            },
            // 元素位置
            offset: function (element) {
                return {
                    top: element.getBoundingClientRect().top,
                    left: element.getBoundingClientRect().left,
                    width: element.getBoundingClientRect().width
                }
            },
            // 对象转化为css字符串
            getStyle: function (object) {
                var cssStr = ""
                for (var key in object) {
                    cssStr += key + ":" + object[key] + ";"
                }
                return cssStr
            },
            // 驼峰转连字符
            toCSSStr(str){
                return str.replace(/([A-Z])/g,"-$1").toLowerCase();
            },
            //js 添加浏览器兼容前缀
            prefixStyle(style) {
                var vendor = this.vendor()
                if (!vendor) {
                    return false
                }
                if (vendor === "standard") {
                    return style
                }
                // return vendor + style.charAt(0).toUpperCase() + style.substr(1);
                return "-" + vendor + "-" + style;
            },
            // 获得浏览器前缀
            vendor: function () {
                var elementStyle = document.createElement("div").style;
                var transformNames = {
                    webkit: "webkitTransform",
                    Moz: "MozTransform",
                    O: "OTransform",
                    ms: "msTransform",
                    standard: "transform"
                }
                for (var key in transformNames) {
                    if (elementStyle[transformNames[key]] !== "undefined") {
                        return key
                    }
                }
                return false
            }
        }
        return core
    }, "wavesBtn")
    new wavesBtn()