Question

What am I doing wrong?

This gives med 4 numbers

d = new Date();
dag = d.getDate();
manad = d.getMonth();
manad++;
ar = d.getFullYear();

alert(ar+manad+dag);

This gives me 8 numbers: the only difference is the ”+ in the alert message

d = new Date();
dag = d.getDate();
manad = d.getMonth();
manad++;
ar = d.getFullYear();
alert('' + ar+manad+dag);

Answer 1

In your first example it’s doing a javascript add of the numbers together. In the second example it’s doing a concatenation because it thinks it’s a string.

The output of the first example would be the day – 13, month – 11 then add 1, year = 2011 so it would be 13 +12 + 2011 = 2036

The second example would be 20111213, year – month + 1, day