js格式化时间

js格式化时间

// 格式化时间 demo:  parseTime(new Date(), '{y}-{m}-{d} {h}:{i}:{s}')
function parseTime(time, pattern) {
    if (arguments.length === 0 || !time) {
        return null;
    }
    const format = pattern || "{y}-{m}-{d} {h}:{i}:{s}";
    let date;
    if (typeof time === "object") {
        date = time;
    } else {
        if (typeof time === "string" && /^[0-9]+$/.test(time)) {
            time = parseInt(time);
        } else if (typeof time === "string") {
            time = time
                .replace(new RegExp(/-/gm), "/")
                .replace("T", " ")
                .replace(new RegExp(/\.[\d]{3}/gm), "");
        }
        if (typeof time === "number" && time.toString().length === 10) {
            time = time * 1000;
        }
        date = new Date(time);
    }
    const formatObj = {
        y: date.getFullYear(),
        m: date.getMonth() + 1,
        d: date.getDate(),
        h: date.getHours(),
        i: date.getMinutes(),
        s: date.getSeconds(),
        a: date.getDay(),
    };
    const time_str = format.replace(/{(y|m|d|h|i|s|a)+}/g, (result, key) => {
        let value = formatObj[key];
        // Note: getDay() returns 0 on Sunday
        if (key === "a") {
            return ["日", "一", "二", "三", "四", "五", "六"][value];
        }
        if (result.length > 0 && value < 10) {
            value = "0" + value;
        }
        return value || 0;
    });
    return time_str;
}

// demo
parseTime(new Date(), '{y}-{m}-{d} {h}:{i}:{s}')