Calculate today's and today's dates for the last January

var date=new date ();

function GetDay (date) {

var year=date.getfullyear ();

var mon=date.getmonth ();

var day=date.getdate ();

var tomon=mon<10? (' 0 ' +mon): Mon;

var today=day<10? (' 0 ' +day):d ay;

var nowdate=year+ '-' +tomon+ '-' +today;

var arr=[' 0 ', ' 31 ', ' 28 ', ' 31 ', ' 30 ', ' 31 ', ' 30 ', ' 31 ', ' 31 ', ' 30 ', ' 31 ', ' 30 ', ' 31 '];

if (mon-1<=0)

{

Year=year-1;

mon=12;

}

Else

{

mon=mon-1;

}

if (Isleapyear (year))

{

arr[2]= ' 29 ';

}

Day=day>=arr[mon]?arr[mon]:d ay;

Day=day<10? (' 0 ' +day):d ay;

Mon=mon<10? (' 0 ' +mon): Mon;

var lastmonth=year+ "-" +mon+ "-" +day;

return{"Nowdate": Nowdate, "Lastmonth": Lastmonth}

}

JS Judge leap Year code
function Isleapyear (year) {
if (((4) ==0) && ((year% 100)!=0) | | ((year% 400) ==0))
{
return (true);
}
Else
{
return (false);
}
}

Calculate today's and today's dates for the last January