Invalid date generated with Javascript
I have a problem that seems so pointless that I'm sure I'm missing something really stupid. I have the following Javascript function that checks for a date:
function validateDate(date){
var re = /\b\d{1,2}[\/-]\d{1,2}[\/-]\d{4}\b/;
if(!re.test(date))
return false;
var separator = (date.indexOf("/") != -1) ? "/" : "-";
var aux = date.split(separator);
var day = parseInt(aux[0]);
var month = parseInt(aux[1]);
var year = parseInt(aux[2]);
alert(aux[0]+" "+aux[1]+" "+aux[2]);
var dateTest = new Date(year,month-1,day);
alert(dateTest); //2nd alert
if(dateTest.getDate() != day)
return false;
if(dateTest.getMonth()+1!= month)
return false;
if(dateTest.getFullYear() != year)
return false;
return true;
}
the first warning always shows the correct values. if the incoming date, for example 05/07/2011
, everything works fine. The second warning displays "Tue Jul 5 00:00:00 UTC+0200 2011"
what is true. but now if I change the date of the month to August or September the date created is wrong. for example with a date 05/08/2011
, a second warning will show "Sun Dec 5 00:00:00 UTC+0100 2010"
.
does anyone know what might be going on?
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Make sure you set the radius parseInt
. If you don't, it will "guess" based on the string. In this case, yours is 08
parsed as an octal value because of the zero prefix and you get 0
back.
var day = parseInt(aux[0], 10);
var month = parseInt(aux[1], 10);
var year = parseInt(aux[2], 10);
Supplying a base ten digit number will give you the correct result.
//Parsing numbers:
parseInt("06"); // 6, valid octal
parseInt("07"); // 7, valid octal
parseInt("08"); // 0, invalid octal
parseInt("09"); // 0, invalid octal
parseInt("10"); // 10, parsed as decimal
parseInt("11"); // 11, parsed as decimal
parseInt("12"); // 12, parsed as decimal
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