uniapp封装缓存方法,设置过期时间

        //缓存,默认有效期28天
			 cache:function(key, value, seconds) {
				var timestamp = Date.parse(new Date()) / 1000
				 console.log(timestamp+"==="+key)
				if (key && value === null) {
					//删除缓存
					//获取缓存
					var val = uni.getStorageSync(key);
					var tmp = val.split("|")
					if (!tmp[1] || timestamp >= tmp[1]) {
						console.log("key已失效")
						uni.removeStorageSync(key)
						return ""
					} else {
						console.log("key未失效")
						return tmp[0]
					}
				} else if (key && value) {
					//设置缓存
					if (!seconds) {
						var expire = timestamp + (3600 * 24 * 28)
					}else{
						var expire = timestamp + seconds
					}
					value = value + "|" + expire
					uni.setStorageSync(key, value);
				} else {
					console.log("key不能空")
				}