1、路由传参：
params传参，刷新会被刷掉
query刷新不掉
storage最老实的办法
vuex也可
2、判断输入是否为空
isNull( str ){
if ( str == "" ) return true;
var regu = "^[ ]+$";
var re = new RegExp(regu);
return re.test(str);
}
if(this.isNull(this.username)){
this.$toast('请输入内容')
return
}
3、时间戳转换时间：
changetimestyle(times){
var a, jsdate=((times) ? new Date(times*1000) : new Date());
var pad = function(n, c){
if((n = n + "").length < c){
return new Array(++c - n.length).join("0") + n;
} else {
return n;
}
};
var txt_weekdays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
var txt_ordin = {1:"st", 2:"nd", 3:"rd", 21:"st", 22:"nd", 23:"rd", 31:"st"};
var txt_months = ["", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
var f = {
// Day
d: function(){return pad(f.j(), 2)},
D: function(){return f.l().substr(0,3)},
j: function(){return jsdate.getDate()},
l: function(){return txt_weekdays[f.w()]},
N: function(){return f.w() + 1},
S: function(){return txt_ordin[f.j()] ? txt_ordin[f.j()] : 'th'},
w: function(){return jsdate.getDay()},
z: function(){return (jsdate - new Date(jsdate.getFullYear() + "/1/1")) / 864e5 >> 0},
// Week
W: function(){
var a = f.z(), b = 364 + f.L() - a;
var nd2, nd = (new Date(jsdate.getFullYear() + "/1/1").getDay() || 7) - 1;
if(b <= 2 && ((jsdate.getDay() || 7) - 1) <= 2 - b){
return 1;
} else{
if(a <= 2 && nd >= 4 && a >= (6 - nd)){
nd2 = new Date(jsdate.getFullYear() - 1 + "/12/31");
return date("W", Math.round(nd2.getTime()/1000));
} else{
return (1 + (nd <= 3 ? ((a + nd) / 7) : (a - (7 - nd)) / 7) >> 0);
}
}
},
// Month
F: function(){return txt_months[f.n()]},
m: function(){return pad(f.n(), 2)},
M: function(){return f.F().substr(0,3)},
n: function(){return jsdate.getMonth() + 1},
t: function(){
var n;
if( (n = jsdate.getMonth() + 1) == 2 ){
return 28 + f.L();
} else{
if( n & 1 && n < 8 || !(n & 1) && n > 7 ){
return 31;
} else{
return 30;
}
}
},
// Year
L: function(){var y = f.Y();return (!(y & 3) && (y % 1e2 || !(y % 4e2))) ? 1 : 0},
Y: function(){return jsdate.getFullYear()},
y: function(){return (jsdate.getFullYear() + "").slice(2)},
// Time
a: function(){return jsdate.getHours() > 11 ? "pm" : "am"},
A: function(){return f.a().toUpperCase()},
B: function(){
var off = (jsdate.getTimezoneOffset() + 60)*60;
var theSeconds = (jsdate.getHours() * 3600) + (jsdate.getMinutes() * 60) + jsdate.getSeconds() + off;
var beat = Math.floor(theSeconds/86.4);
if (beat > 1000) beat -= 1000;
if (beat < 0) beat += 1000;
if ((String(beat)).length == 1) beat = "00"+beat;
if ((String(beat)).length == 2) beat = "0"+beat;
return beat;
},
g: function(){return jsdate.getHours() % 12 || 12},
G: function(){return jsdate.getHours()},
h: function(){return pad(f.g(), 2)},
H: function(){return pad(jsdate.getHours(), 2)},
i: function(){return pad(jsdate.getMinutes(), 2)},
s: function(){return pad(jsdate.getSeconds(), 2)},
O: function(){
var t = pad(Math.abs(jsdate.getTimezoneOffset()/60*100), 4);
if (jsdate.getTimezoneOffset() > 0) t = "-" + t; else t = "+" + t;
return t;
},
P: function(){var O = f.O();return (O.substr(0, 3) + ":" + O.substr(3, 2))},
c: function(){return f.Y() + "-" + f.m() + "-" + f.d() + "T" + f.h() + ":" + f.i() + ":" + f.s() + f.P()},
U: function(){return Math.round(jsdate.getTime()/1000)}
};
var dateStr = 'Y-m-d H:i:s' ;//xxxx-x-x x:x:x
//var dateStr = 'Y-m-d';//xxxx-x-x
return dateStr.replace(/[\\]?([a-zA-Z])/g, function(t, s){
var ret;
if( t!=s ){
ret = s;
} else if( f[s] ){
ret = f[s]();
} else{
ret = s;
}
return ret;
});
},
4、localstorage存储和获取数组、对象（原文：https://www.cnblogs.com/ranyonsue/p/6402687.html）
过期策略：localstorage永久存储，不过期，除非手动删除，sessionstorage在重启浏览器、关闭页面或新开页面时失效。
demo:
var obj = {};
var str = JSON.stringify(obj);
//存入
localstorage.obj = str;
//读取
str = localstorage.obj;
//重新转换为对象
obj = JSON.parse(str);
5、验证码倒计时：
var waits=59;
var timers = setInterval(() => {
if(waits < 1){
waits=1;
clearTimeout(timers)
_this.txts = '获取验证码'
}else{
_this.txts = waits+'秒后重发'
waits--;
}
}, 1000)
6、抢购倒计时（endDateStr为时间戳格式）
TimeDown(id,endDateStr) {
var endDate = (new Date(endDateStr)).valueOf();
//当前时间
var nowDate = (new Date()).valueOf();
//相差的总秒数
var totalSeconds = parseInt((endDate*1000 - nowDate) / 1000);
//天数
var days = Math.floor(totalSeconds / (60 * 60 * 24));
//取模（余数）
var modulo = totalSeconds % (60 * 60 * 24);
//小时数
var hours = Math.floor(modulo / (60 * 60));
modulo = modulo % (60 * 60);
//分钟
var minutes = Math.floor(modulo / 60);
//秒
var seconds = modulo % 60;
this.djscont = "还剩:" + days + "天" + hours + "小时" + minutes + "分钟" + seconds + "秒";
//延迟一秒执行自己
let that = this
setTimeout(function () {
that.TimeDown(id, endDateStr);
}, 1000)
},
未完待续。。。。。