JavaScript calculates the day difference of of between two dates

2020-03-30 01:06:33
OfStack

One: calculate the number of days between two dates

For example:
Str1 = "2002-01-20"
Str2 = "2002-10-11"
How do you calculate the number of days between str1 and str2 using javaScript?


<html>  
<head>  
<meta  http-equiv="Content-Type"  content="text/html;  charset=gb2312">  
<title></title>  
</head>  

<body>  
<button  onClick="btnCount_Click()"> Counting days off </button>  
<script  language="JavaScript">  

   function  btnCount_Click(){  
       s1  =  "2002-1-10"  
       s2  =  "2002-10-1"  
       alert(DateDiff(s1,s2))  
   }  

   //A function of the number of days, universal & PI;
   function  DateDiff(sDate1,  sDate2){    //SDate1 and sDate2 are in 2002-12-18 format & NBSP;
       var  aDate,  oDate1,  oDate2,  iDays  
       aDate  =  sDate1.split("-")  
       oDate1  =  new  Date(aDate[1]  +  '-'  +  aDate[2]  +  '-'  +  aDate[0])    //Convert to 12-18-2002 & NBSP;
       aDate  =  sDate2.split("-")  
       oDate2  =  new  Date(aDate[1]  +  '-'  +  aDate[2]  +  '-'  +  aDate[0])  
       iDays  =  parseInt(Math.abs(oDate1  -  oDate2)  /  1000  /  60  /  60  /24)    //Converts the number of milliseconds off into the number of days & NBSP;
       return  iDays  
}

Two: calculate the date after a certain number of days

In JavaScript, you calculate what the days after the date of the day are. Far from being as convenient as it is in.net, a function can solve the problem. On this problem, I puzzled for a period of time, and finally through the introduction of a net friend to solve the problem. Post it and share it.


<script  language="javascript"  type="text/javascript">  
var  startDate  =  new  Date  ();           var  intValue  =  0;  
var  endDate  =  null;  

intValue  =  startDate.getTime();            intValue  +=  100  *  (24  *  3600  *  1000);  
endDate  =  new  Date  (intValue);  
alert  (endDate.getFullYear()+"-"+ (endDate.getMonth()+1)+"-"+ endDate.getDate());  
</script>

The 100 above represents the date after 100 days, which you can change. Date.getTime() in JS, can only be 1970.01.01 after the Date; There are months are 0-11, a little different, avoid oh. Of course, you can also calculate the date after a certain date.


<script  language="javascript"  type="text/javascript">  
var  startDate  =  new  Date  (2007,  (8-1),  1,  10,  10,  10);
var  intValue  =  0;  
var  endDate  =  null;  

intValue  =  startDate.getTime();            intValue  +=  100  *  (24  *  3600  *  1000);
endDate  =  new  Date  (intValue);  
alert  (endDate.getFullYear()+"-"+ (endDate.getMonth()+1)+"-"+ endDate.getDate());  
</script>