Unity 使用this关键字进行函数拓展 - DateTime

Example：

using System;
using UnityEngine;

using SK.Framework;

public class Foo : MonoBehaviour
{
    private void Start()
    {
        DateTime dt = DateTime.Now;

        //周六
        dt.DayOfWeek.ToChinese();
        //星期六
        dt.DayOfWeek.ToChinese2();

        //yyyy/MM/dd
        dt.ToDateString();
        //yyyy-MM-dd
        dt.ToDateString2();
        //yyyy年MM月dd日
        dt.ToDateString3();

        //yyyy/MM/dd HH:mm:ss
        dt.ToDateTimeString();
        //yyyy-MM-dd HH:mm:ss
        dt.ToDateTimeString2();
        //yyyy年MM月dd日 HH:mm:ss
        dt.ToDateTimeString3();
    }
}

Extension：

using System;

namespace SK.Framework
{
    /// 
    /// DateTime日期时间类相关拓展
    /// 
    public static class DateTimeExtension
    {
        /// 
        /// 获取时间戳
        /// 
        /// 时间
        /// 时间戳
        public static double GetTimeStamp(this DateTime self)
        {
            //计算机元年 1970年1月1日0时0分0秒
            return (self - new DateTime(1970, 1, 1, 0, 0, 0, 0)).TotalSeconds;
        }
        /// 
        /// 转换为中文 （周*）
        /// 
        /// 
        /// 
        public static string ToChinese(this DayOfWeek self)
        {
            switch (self)
            {
                case DayOfWeek.Monday: return "周一";
                case DayOfWeek.Tuesday: return "周二";
                case DayOfWeek.Wednesday: return "周三";
                case DayOfWeek.Thursday: return "周四";
                case DayOfWeek.Friday: return "周五";
                case DayOfWeek.Saturday: return "周六";
                case DayOfWeek.Sunday: return "周日";
                default: return null;
            }
        }
        /// 
        /// 转换为中文 （星期*）
        /// 
        /// 
        /// 
        public static string ToChinese2(this DayOfWeek self)
        {
            switch (self)
            {
                case DayOfWeek.Monday: return "星期一";
                case DayOfWeek.Tuesday: return "星期二";
                case DayOfWeek.Wednesday: return "星期三";
                case DayOfWeek.Thursday: return "星期四";
                case DayOfWeek.Friday: return "星期五";
                case DayOfWeek.Saturday: return "星期六";
                case DayOfWeek.Sunday: return "星期日";
                default: return null;
            }
        }
        /// 
        /// 转换格式 yyyy/MM/dd
        /// 
        /// 
        /// yyyy/MM/dd
        public static string ToDateString(this DateTime self)
        {
            return self.ToString("yyyy/MM/dd");
        }
        /// 
        /// 转换格式 yyyy-MM-dd
        /// 
        /// 
        /// yyyy-MM-dd
        public static string ToDateString2(this DateTime self)
        {
            return self.ToString("yyyy-MM-dd");
        }
        /// 
        /// 转换格式 yyyy年MM月dd日
        /// 
        /// 
        /// yyyy年MM月dd日
        public static string ToDateString3(this DateTime self)
        {
            return self.ToString("yyyy年MM月dd日");
        }
        /// 
        /// 转换格式 yyyy/MM/dd HH:mm:ss
        /// 
        /// 
        /// yyyy/MM/dd HH:mm:ss
        public static string ToDateTimeString(this DateTime self)
        {
            return self.ToString("yyyy/MM/dd HH:mm:ss");
        }
        /// 
        /// 转换格式 yyyy-MM-dd HH:mm:ss
        /// 
        /// 
        /// yyyy-MM-dd HH:mm:ss
        public static string ToDateTimeString2(this DateTime self)
        {
            return self.ToString("yyyy-MM-dd HH:mm:ss");
        }
        /// 
        /// 转换格式 yyyy年MM月dd日 HH:mm:ss
        /// 
        /// 
        /// yyyy年MM月dd日 HH:mm:ss
        public static string ToDateTimeString3(this DateTime self)
        {
            return self.ToString("yyyy年MM月dd日 HH:mm:ss");
        }
    }
}