Go语言time包的练习及封装

把time包相关的函数用法过了下,基本包含大部份常见的用法了.
并封装了下日期显示格式定制及time.Time数组排序的功能.以便以后调用.

保留下测试所用例子:     

package main 

//author:xcl
//2014-1-14

import (
	"fmt"
	"time"
    "github.com/xclpkg/utils"
    "sort"
)

func main(){

    t := time.Now();
    //alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';
    //select to_date('2014-06-09 18:04:06','yyyy-MM-dd HH24:mi:ss') as dt from dual;
    fmt.Println("\n演示时间 => ",utils.GetTmShortStr(t,"y-m-d H:i:s a"))

    //返回当前是一年中的第几天
    //select to_char(sysdate,'ddd'),sysdate from dual;
    yd := t.YearDay();
    fmt.Println("一年中的第几天: ",yd)       

    //一年中的第几周
    year,week := t.ISOWeek()
    fmt.Println("一年中的第几周: ",year," | ",week)       

    //当前是周几
    //select to_char(sysdate,'day') from dual;
    //select to_char(sysdate,'day','NLS_DATE_LANGUAGE = American') from dual;   
    fmt.Println("当前是周几: ",t.Weekday().String())

    //字符串转成time.Time
    //alter session set nls_date_format='yyyy-mm-dd hh:mi:ss';
    //select to_date('14-06-09 6:04:06','yy-MM-dd hh:mi:ss') as dt from dual;    
    tt,er := time.Parse(utils.GoStdTime(),"2014-06-09 16:04:06")
    if(er != nil){
        fmt.Println("字符串转时间: parse error!")
    }else{
        fmt.Println("字符串转时间: ",tt.String())
    }


    fmt.Println("\n演示时间 => ",utils.GetTmStr(t,"y-m-d h:i:s"))
   
    ta := t.AddDate(1,0,0)   
    fmt.Println("增加一年 => ",utils.GetTmStr(ta,"y-m-d"))
 
    ta = t.AddDate(0,1,0)
    fmt.Println("增加一月 => ",utils.GetTmStr(ta,"y-m-d"))

    //select sysdate,sysdate + interval '1' day from dual;
    ta = t.AddDate(0,0,1) //18
    fmt.Println("增加一天 => ",utils.GetTmStr(ta,"y-m-d"))

    durdm,_ := time.ParseDuration("432h")
    ta = t.Add(durdm)
    fmt.Println("增加18天(18*24=432h) => ",utils.GetTmStr(ta,"y-m-d"))
 
    //select sysdate,sysdate - interval '7' hour from dual;
    dur,_ := time.ParseDuration("-2h")
    ta = t.Add(dur)
    fmt.Println("减去二小时 => ",utils.GetTmStr(ta,"y-m-d h:i:s"))

    //select sysdate,sysdate - interval '7' MINUTE from dual;
    durmi,_ := time.ParseDuration("-7m")
    ta = t.Add(durmi)
    fmt.Println("减去7分钟 => ",utils.GetTmStr(ta,"y-m-d h:i:s"))

    //select sysdate,sysdate - interval '10' second from dual;
    durs,_ := time.ParseDuration("-10s")
    ta = t.Add(durs)
    fmt.Println("减去10秒 => ",utils.GetTmStr(ta,"y-m-d h:i:s"))

    ttr,er := time.Parse(utils.GoStdTime(),"2014-06-09 16:58:06")
    if(er != nil){
        fmt.Println("字符串转时间: 转换失败!")
    }else{
        fmt.Println("字符串转时间: ",ttr.String())
    }

    //alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';
    //select trunc(to_date('2014-06-09 16:58:06','yyyy-mm-dd hh24:mi:ss'),'mi') as dt from dual; 
    // SQL => 2014-06-09 16:58:00
    // Truncate =>  2014-06-09 16:50:00
    durtr,_ := time.ParseDuration("10m")
    ta = ttr.Truncate(durtr)
    fmt.Println("Truncate => ",utils.GetTmStr(ta,"y-m-d H:i:s"))

    //select round(to_date('2014-06-09 16:58:06','yyyy-mm-dd hh24:mi:ss'),'mi') as dt from dual; 
    // SQL => 2014-06-09 16:58:00
    // Round =>  2014-06-09 17:00:00
    ta = ttr.Round(durtr)
    fmt.Println("Round => ",utils.GetTmStr(ta,"y-m-d H:i:s"))

    //日期比较
    tar1,_ := time.Parse(utils.GoStdTime(),"2014-06-09 19:38:36")
    tar2,_ := time.Parse(utils.GoStdTime(),"2015-01-14 17:08:26")
    if tar1.After(tar2) {
        fmt.Println("tar1 > tar2")
    }else if tar1.Before(tar2) {
        fmt.Println("tar1 < tar2")
    }else{
        fmt.Println("tar1 = tar2")
    }
    tar3,_ := time.Parse(utils.GoStdTime(),"2000-07-19 15:58:16")

    //日期列表中最晚日期
    // select greatest('2014-06-09','2015-01-14','2000-07-19') from dual;    
    var arr utils.TimeSlice
    arr = []time.Time{tar1,tar2,tar3}
    temp := utils.Greatest(arr)
    fmt.Println("日期列表中最晚日期 => ",utils.GetTmStr(temp,"y-m-d"))    

    //日期数组从早至晚排序
    fmt.Println("\n日期数组从早至晚排序")
    sort.Sort(arr)
    for _,at := range arr {
         fmt.Println("Sort => ",utils.GetTmStr(at,"y-m-d H:i:s"))
    }

}

      AddDate与ParseDuration有个区别需要注意:
             在AddDate中各位置是独立的.既在对应位置的更改,不会影响其它位置的值,如日期add超过月底(30/31),月份不会自动增加,而日期则会变更为01.
             但ParseDuration则不同,是针对整个time.Time的变更.

       例子中将Oracle相关功能的SQL实现,也简单的附注了下.日期时间处理其实蛮复杂的,

查查Oracle的Date和Timestamp相关知识就知道要考虑多少东西了.

time包能封装的这么简洁真不容易.

         我自己封装的包放在此: github

MAIL: xcl_168@aliyun.com

BLOG:http://blog.csdn.net/xcl168

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