Can you help me to understand why d1 has different value in each alert() ? Thanks.
<script>
d1 = new Date("01/01/2015");
d2 = d1;
alert(d1);
d2.setDate(d2.getDate()+10);
alert(d1);
</script>
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MarcioAB
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BTW, using the Date constructor to parse date strings is not a good idea. – RobG Oct 12 '15 at 01:00
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Because objects are reference types, and in the line d2 = d1 a pointer is passed to d2 that points to d1 and if you d2.setDate(d2.getDate()+10); execute this line is same as you edited d1.setDate(d1.getDate()+10);
IamK
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Well, the value of the variable *d1* is a reference and `d2 = d1` copies the reference and assigns it to *d2* so that both variables reference the same Date object. – RobG Oct 12 '15 at 01:01
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Thank you. So, as Date is an object and just copy the pointer. So, I need to create a new object and copy it like this – MarcioAB Oct 12 '15 at 03:32