封装的缓存功能，兼容网页，微信小程序，uni-app 使用，支持设置缓存，获取缓存，移除缓存，清空缓存，设置缓存时间，分组缓存设置。
把最下面的 Str4.js 代码拷贝到项目内可以直接使用，调用方式见下面的代码调用示例
封装的Js 文件在 uni-app 目录结构图：
uni-app 调用示例
<template>
<view class="content">
<view>{{testKey1}}</view>
<view>{{testKey2}}</view>
<view>{{testKey3}}</view>
</view>
</template>
<script>
import Str4 from '@/common/js/Str4.js';
export default {
data() {
return {
testKey1: 'AAA',
testKey2: 'VVV',
testKey3: '',
}
},
mounted: function() {
// 保存
Str4.localStorage.set('testKey1','1111111111');
Str4.localStorage.set('testKey2','222222222');
Str4.localStorage.set('testKey3','333333333');
//读取
this.testKey1 = Str4.localStorage.get('testKey1');
this.testKey2 = Str4.localStorage.get('testKey2');
this.testKey3 = Str4.localStorage.get('testKey3');
}
}
</script>
<style>
.content {}
</style>
h5调用示例
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<script type="text/javascript" src="./js/Str4.js"></script>
</head>
<body>
<div id="testKey1"></div>
<div id="testKey2"></div>
<div id="testKey3"></div>
<script>
// 1、保存
Str.localStorage.set('testKey1', '我已经保存111111', 3600, 'group');
Str.localStorage.set('testKey2', '我已经保存222222', 0, 'group');
Str.localStorage.set('testKey3', '我已经保存333333', 0.01);
// 2、读取
var key1 = Str.localStorage.get('testKey1','group');
document.getElementById('testKey1').innerText = key1;
var key2 = Str.localStorage.get('testKey2','group');
document.getElementById('testKey2').innerText = key2;
var key3 = Str.localStorage.get('testKey3');
document.getElementById('testKey3').innerText = key3;
//Str.localStorage.remove('group');
/* // 3、修改
Str.localStorage.set('testKey2','我被修改了222');
var key2 = Str.localStorage.get('testKey2');
document.getElementById('testKey2').innerText = key2;
// 4、删除指定键
Str.localStorage.remove('testKey3');
var key3 = Str.localStorage.get('testKey3');
document.getElementById('testKey3').innerText = key3; */
// 5、清空
//Str.localStorage.clear();
</script>
</body>
</html>
Str4.js 代码封装：
var Str = {};
/*
* 判断字符串是否为空
*/
Str.isNull = function(str) {
if (str === undefined) return true;
if (str === 'undefined') return true;
if (str === null) return true;
if (typeof str == 'string') str = str.replace(/^\s*|\s*$/g, "");
if (str === '') return true;
return false;
};
/*
* 判断字符串是否为非空
*/
Str.isNotNull = function(str) {
return !this.isNull(str);
};
/**
* localStorage操作
*/
Str.localStorage = {
/**
* 保存
* @param {Object} key 键名
* @param {Object} value 键值
* @param int second 缓存时间（单位：秒)
* @param string ctag 组名
*/
set: function(key, value, second = null, ctag = null) {
if (Str.isNull(second) || second == 0) second = 86400 * 365 * 10;
var data = {
value: value,
expire: parseInt((new Date()).getTime() / 1000) + second
};
if (Str.isNotNull(ctag)) {
// 如果存在组主键名，则保存在组主键下
let baseVal = this.get(ctag) || {};
baseVal[key] = data;
data = {
value: baseVal,
expire: parseInt(new Date().getTime() / 1000) + 86400 * 365 * 10
};
key = ctag;
}
if (localStorage != undefined) {
localStorage.setItem(key, JSON.stringify(data));
} else if (uni.setStorageSync != undefined) {
uni.setStorageSync(key, JSON.stringify(data));
} else if (wx.setStorageSync != undefined) {
wx.setStorageSync(key, JSON.stringify(data));
}
},
/**
* 读取
* @param {Object} key 键名
*/
get: function(key, ctag) {
let _key = key;
if (Str.isNotNull(ctag)) {
key = ctag; // 如果存在组主键名，则读取组主键内容
}
var data = null;
if (localStorage != undefined) {
data = localStorage.getItem(key);
} else if (uni.getStorageSync != undefined) {
data = uni.getStorageSync(key);
} else if (wx.getStorageSync != undefined) {
data = wx.getStorageSync(key);
}
if (Str.isNotNull(data)) {
if (typeof data == 'string') data = JSON.parse(data);
if (Str.isNotNull(ctag)) {
if (data.expire != null && data.expire * 1000 < new Date().getTime()) {
this.remove(ctag);
return null;
}
data = data.value[_key]; // 重新赋值
if (Str.isNull(data)) return null;
}
if (data.expire != null && data.expire * 1000 < new Date().getTime()) {
this.remove(_key, ctag);
return null;
}
return data.value;
}
return null;
},
/**
* 删除指定键
* @param key 键名
* @param ctag 组主键名
*/
remove: function(key, ctag) {
if (Str.isNotNull(ctag)) {
if (Str.isNull(key)) {
key = ctag;
} else {
let baseVal = this.get(ctag) || {};
delete baseVal[key];
if (JSON.stringify(baseVal) == '{}') key = ctag;
else this.set(ctag, baseVal, null);
}
}
if (localStorage != undefined) {
localStorage.removeItem(key);
} else if (uni.removeStorageSync != undefined) {
uni.removeStorageSync(key);
} else if (wx.removeStorageSync != undefined) {
wx.removeStorageSync(key);
}
},
/**
* 清空
*/
clear: function() {
if (localStorage != undefined) {
localStorage.clear();
} else if (uni.clearStorageSync != undefined) {
uni.clearStorageSync();
} else if (wx.clearStorageSync != undefined) {
wx.clearStorageSync();
}
}
};
if (typeof module != 'undefined') module.exports = Str;
