Shulou(Shulou.com)06/02 Report--

这篇文章主要为大家展示了微信小程序开发中回到顶部怎么做，内容简而易懂，条理清晰，希望能够帮助大家解决疑惑，下面让小编带大家一起来研究并学习一下"微信小程序开发中回到顶部怎么做"这篇文章吧。

1、如何实现点击返回顶层？

最近在研究微信小程序，被这个返回顶层给坑了一波，下面贴代码

wxml代码：

template>block>scroll-view> contact-button>客服view>电话view>顶层view>

js代码：

var app = getApp();Page({data: {hidden: true,list: [],scrollTop: {scroll_top: 0,goTop_show: false},scrollHeight: 0,floorstatus:true,sortArr:[{id: 1,img: "../../images/2.jpg",title: "君御豪园住宅",introduction: "杭州不限购不限贷口住宅",money: 5000,vperson: 115,tperson: 0}],},scrollTopFun: function (e) {console.log(e.detail);if (e.detail.scrollTop > 300) {//触发gotop的显示条件 this.setData({'scrollTop.goTop_show': true});} else {this.setData({'scrollTop.goTop_show': false});}},goTopFun: function (e) {var _top = this.data.scrollTop.scroll_top;//发现设置scroll-top值不能和上一次的值一样，否则无效，所以这里加了个判断 if (_top == 0) {_top = 1;} else {_top = 0;}this.setData({'scrollTop.scroll_top': _top});},/*** 生命周期函数--监听页面加载*/onLoad: function (options) {var that = this;wx.getSystemInfo({success: function (res) {that.setData({scrollHeight: res.windowHeight});}});},}）

wxss代码：

.fliexBox{width: 100rpx;height: 50rpx;background-color: #5db13b;color: #ffffff;text-align: center;position: fixed;right: 0rpx;bottom: 85rpx;border-radius: 20rpx 0rpx 0rpx 20rpx;font-size: 26rpx;line-height: 50rpx;opacity: .6;}.callOur{bottom: 20rpx;}contact-button{opacity: 0;position: absolute;}

主要是需要把scroll-view 组件的高度设置起来而且不能是百分比 如100%这样，可以是rpx，这样才可以监测到滑动的距离。

2、微信小程序md5加密

/* * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message * Digest Algorithm, as defined in RFC 1321. * Version 1.1 Copyright (C) Paul Johnston 1999 - 2002. * Code also contributed by Greg Holt * See http://pajhome.org.uk/site/legal.html for details. */ /* * Add integers, wrapping at 2^32. This uses 16-bit operations internally * to work around bugs in some JS interpreters. */ function safe_add(x, y) { var lsw = (x & 0xFFFF) + (y & 0xFFFF) var msw = (x >> 16) + (y >> 16) + (lsw >> 16) return (msw > (32 - cnt)) } /* * These functions implement the four basic operations the algorithm uses. */ function cmn(q, a, b, x, s, t) { return safe_add(rol(safe_add(safe_add(a, q), safe_add(x, t)), s), b) } function ff(a, b, c, d, x, s, t) { return cmn((b & c) | ((~b) & d), a, b, x, s, t) } function gg(a, b, c, d, x, s, t) { return cmn((b & d) | (c & (~d)), a, b, x, s, t) } function hh(a, b, c, d, x, s, t) { return cmn(b ^ c ^ d, a, b, x, s, t) } function ii(a, b, c, d, x, s, t) { return cmn(c ^ (b | (~d)), a, b, x, s, t) } /* * Calculate the MD5 of an array of little-endian words, producing an array * of little-endian words. */ function coreMD5(x) { var a = 1732584193 var b = -271733879 var c = -1732584194 var d = 271733878 for(var i = 0; i

< x.length; i += 16) { var olda = a var oldb = b var oldc = c var oldd = d a = ff(a, b, c, d, x[i+ 0], 7 , -680876936) d = ff(d, a, b, c, x[i+ 1], 12, -389564586) c = ff(c, d, a, b, x[i+ 2], 17, 606105819) b = ff(b, c, d, a, x[i+ 3], 22, -1044525330) a = ff(a, b, c, d, x[i+ 4], 7 , -176418897) d = ff(d, a, b, c, x[i+ 5], 12, 1200080426) c = ff(c, d, a, b, x[i+ 6], 17, -1473231341) b = ff(b, c, d, a, x[i+ 7], 22, -45705983) a = ff(a, b, c, d, x[i+ 8], 7 , 1770035416) d = ff(d, a, b, c, x[i+ 9], 12, -1958414417) c = ff(c, d, a, b, x[i+10], 17, -42063) b = ff(b, c, d, a, x[i+11], 22, -1990404162) a = ff(a, b, c, d, x[i+12], 7 , 1804603682) d = ff(d, a, b, c, x[i+13], 12, -40341101) c = ff(c, d, a, b, x[i+14], 17, -1502002290) b = ff(b, c, d, a, x[i+15], 22, 1236535329) a = gg(a, b, c, d, x[i+ 1], 5 , -165796510) d = gg(d, a, b, c, x[i+ 6], 9 , -1069501632) c = gg(c, d, a, b, x[i+11], 14, 643717713) b = gg(b, c, d, a, x[i+ 0], 20, -373897302) a = gg(a, b, c, d, x[i+ 5], 5 , -701558691) d = gg(d, a, b, c, x[i+10], 9 , 38016083) c = gg(c, d, a, b, x[i+15], 14, -660478335) b = gg(b, c, d, a, x[i+ 4], 20, -405537848) a = gg(a, b, c, d, x[i+ 9], 5 , 568446438) d = gg(d, a, b, c, x[i+14], 9 , -1019803690) c = gg(c, d, a, b, x[i+ 3], 14, -187363961) b = gg(b, c, d, a, x[i+ 8], 20, 1163531501) a = gg(a, b, c, d, x[i+13], 5 , -1444681467) d = gg(d, a, b, c, x[i+ 2], 9 , -51403784) c = gg(c, d, a, b, x[i+ 7], 14, 1735328473) b = gg(b, c, d, a, x[i+12], 20, -1926607734) a = hh(a, b, c, d, x[i+ 5], 4 , -378558) d = hh(d, a, b, c, x[i+ 8], 11, -2022574463) c = hh(c, d, a, b, x[i+11], 16, 1839030562) b = hh(b, c, d, a, x[i+14], 23, -35309556) a = hh(a, b, c, d, x[i+ 1], 4 , -1530992060) d = hh(d, a, b, c, x[i+ 4], 11, 1272893353) c = hh(c, d, a, b, x[i+ 7], 16, -155497632) b = hh(b, c, d, a, x[i+10], 23, -1094730640) a = hh(a, b, c, d, x[i+13], 4 , 681279174) d = hh(d, a, b, c, x[i+ 0], 11, -358537222) c = hh(c, d, a, b, x[i+ 3], 16, -722521979) b = hh(b, c, d, a, x[i+ 6], 23, 76029189) a = hh(a, b, c, d, x[i+ 9], 4 , -640364487) d = hh(d, a, b, c, x[i+12], 11, -421815835) c = hh(c, d, a, b, x[i+15], 16, 530742520) b = hh(b, c, d, a, x[i+ 2], 23, -995338651) a = ii(a, b, c, d, x[i+ 0], 6 , -198630844) d = ii(d, a, b, c, x[i+ 7], 10, 1126891415) c = ii(c, d, a, b, x[i+14], 15, -1416354905) b = ii(b, c, d, a, x[i+ 5], 21, -57434055) a = ii(a, b, c, d, x[i+12], 6 , 1700485571) d = ii(d, a, b, c, x[i+ 3], 10, -1894986606) c = ii(c, d, a, b, x[i+10], 15, -1051523) b = ii(b, c, d, a, x[i+ 1], 21, -2054922799) a = ii(a, b, c, d, x[i+ 8], 6 , 1873313359) d = ii(d, a, b, c, x[i+15], 10, -30611744) c = ii(c, d, a, b, x[i+ 6], 15, -1560198380) b = ii(b, c, d, a, x[i+13], 21, 1309151649) a = ii(a, b, c, d, x[i+ 4], 6 , -145523070) d = ii(d, a, b, c, x[i+11], 10, -1120210379) c = ii(c, d, a, b, x[i+ 2], 15, 718787259) b = ii(b, c, d, a, x[i+ 9], 21, -343485551) a = safe_add(a, olda) b = safe_add(b, oldb) c = safe_add(c, oldc) d = safe_add(d, oldd) } return [a, b, c, d] } /* * Convert an array of little-endian words to a hex string. */ function binl2hex(binarray) { var hex_tab = "0123456789abcdef" var str = "" for(var i = 0; i < binarray.length * 4; i++) { str += hex_tab.charAt((binarray[i>

>2] >> ((i%4)*8+4)) & 0xF) + hex_tab.charAt((binarray[i>>2] >> ((i%4)*8)) & 0xF) } return str } /* * Convert an array of little-endian words to a base64 encoded string. */ function binl2b64(binarray) { var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" var str = "" for(var i = 0; i

< binarray.length * 32; i += 6) { str += tab.charAt(((binarray[i>

>5] >5+1] >> (32-i%32)) & 0x3F)) } return str } /* * Convert an 8-bit character string to a sequence of 16-word blocks, stored * as an array, and append appropriate padding for MD4/5 calculation. * If any of the characters are >255, the high byte is silently ignored. */ function str2binl(str) { var nblk = ((str.length + 8) >> 6) + 1 // number of 16-word blocks var blks = new Array(nblk * 16) for(var i = 0; i

< nblk * 16; i++) blks[i] = 0 for(var i = 0; i < str.length; i++) blks[i>

>2] |= (str.charCodeAt(i) & 0xFF) >2] |= 0x80 > 5) + 1 // number of 16-word blocks var blks = new Array(nblk * 16) for(var i = 0; i

< nblk * 16; i++) blks[i] = 0 for(var i = 0; i < str.length; i++) blks[i>

>1] |= str.charCodeAt(i) >1] |= 0x80

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