Iterating over numbers with leading zeroes with a `for` loop [duplicate]

This question already has answers here: How to pad single开发者_StackOverflow中文版-digit numbers with a leading 0 (7 answers) Closed 12 months ago.

I'm working on a calendar site and need to change the following code to show 0 before the value of $list_day if it's a single digit number.

for($list_day = 1; $list_day <= $days_in_month; $list_day++):

How should I go about doing this?

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When you're printing it, use sprintf("%02d", $list_day) to pad it with a zero.

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if ($list_day < 10)
  echo "0" . $list_day;
else
  echo $list_day;

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printf("%02d",$listday);


printf("%02d",3);  //prints 03

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echo sprintf('%02d',$list_day);

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You could do this as

for ($list_day = "01"; $list_day <= $days_in_month; $list_day = sprintf("%02d", $list_day + 1))

but it's usually done like

for ($list_day = 1; $list_day <= $days_in_month; $list_day++) {
    print "<div>" . sprintf("%02d", $list_day) . "...</div>";
}

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if($list_day < 10)
    $new_day = '0'.$list_day;
else
    $new_day = $list_day;