How to convert a date formatted (YYMMDD) as string but with 00 days?-CodePudding

I have a date formatted as string, eg: 240800. The date format for that string is YYMMDD. With the below code, I can convert the string to date but it doesn't always work in deducting 1 day. I need my output to be a valid date, not with 00 day. So with the date above, it should be converted and formatted to 07/31/2024.

Here's what I got so far.

function formatDate(stringDate) {
  var year = stringDate.substring(0,2);
  var month = stringDate.substring(2,4);
  var day = stringDate.substring(4,6);
  
  var date = new Date('20'   year, month, day);
  
  var formattedDate = date.getMonth()   '/'   date.getDate()   '/'   date.getFullYear();
  
  console.log(formattedDate);
}

Working:

"240800" = 7/31/2024
All months from 4 to 12

Not Working:

"240100" = 0/31/2024 x
"240200" = 1/29/2024 x
"240300" = 2/31/2024 x

CodePudding user response：

The reason is the date variable parameter in new Date() is counted as 0~11, not the general range,1~12. So the working answer actually is wrong. It seems like being right just for July and August have 31 days. The correct way is to firstly deduct 1 month and then calculate it. After all of the process is done, you can add 1 month in the end. The below is working codes:

function formatDate(stringDate) {
  var year = stringDate.substring(0,2);

  //deduct 1 month firstly
  var month = Number(stringDate.substring(2,4))-1;
  var day = stringDate.substring(4,6);
  var date = new Date('20'   year, month, day);

  //add 1 month finally
  var formattedDate = date.getMonth() 1   '/'   date.getDate()   '/'   date.getFullYear();
  
  console.log(formattedDate);
}
formatDate('240100');

CodePudding user response：

In python Assuming your string is yymmdd below function should do what you want. I am sure javascript has some module for date handling.

from datetime import datetime, timedelta

def fd(s):
    d=datetime.strptime(s[:-2],'%y%m') timedelta(days=int(s[-2:])-1)
    return d.strftime('%m/%d/%Y')

CodePudding user response：

Try this ..

function formatDate(stringDate) {
  var year = stringDate.substring(0,2);
  var month = stringDate.substring(2,4);
  var day = stringDate.substring(4,6);
   
   var d1;
if (day==="00")
{   
  d1 = new Date(month   '/01/20'   year);
d1.setDate(d1.getDate() -1);
   //console.log("day1"   d1);
 }
else
{
   d1 = new Date('20'   year, month, day);
}
   
  var formattedDate = d1.getMonth()   '/'   d1.getDate()   '/'   d1.getFullYear();
 
  console.log(formattedDate);
}