php format a number so that it has leading zero

Question

I want to format my array vars to that numbers under ten have leading zeros, so:

$myArray=array(1,2,3,10,11,100);

So that it is:

$myArray=array(01,02,03,10,11,100);

Is there an easy function for this?

Thanks in advance.

Okay, one way I've thought of is `if(strlen($var)==1)$var="0".$var;` but is there a better way? — user783322, Mar 16 '12 at 11:51
String is fine - it's actually for time "01:59:59", so I'll be strtotime anyway. — user783322, Mar 16 '12 at 11:52
If you're ultimately passing the values through `strtotime()`, why add the zero beforehand? — JJJ, Mar 16 '12 at 11:53
Why use `strtotime` if you have `DateTime::createFromFormat`. — N.B., Mar 16 '12 at 11:57

score 5 · Answer 1 · answered Mar 16 '12 at 11:57

5

In php, a leading zero means the number is a octal number.

You should just format it at the output time like:

$myArray=array(1,2,3,10,11,100);
foreach ($myArray as $var) {
  echo sprintf("%02d\n", $var);
}

answered Mar 16 '12 at 11:57

xdazz

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score 5 · Answer 2 · answered Mar 16 '12 at 14:30

This allows you to pad all values to a variable length.

Keep in mind a leading zero is not a valid integer representation. For portability reasons, If you want to store the values, the values should be converted to strings.

$myArray = array(1,2,3,10,11,100);
$pad_length = 2;

foreach ($myArray as &$item)
{
    $item = str_pad($item, $pad_length, '0', STR_PAD_LEFT);
}

print_r($myArray);

Outputs:

Array
(   
    [0] => 01
    [1] => 02
    [2] => 03
    [3] => 10
    [4] => 11
    [5] => 100
)

Nicola Peluchetti · Answer 3 · 2012-03-16T12:00:34.523

4

It's muche better to add the 0 when you print it otherwise you transform them to string:

$myArray=array(1,2,3,10,11,100);

foreach ($myArray as $number){
    printf("%02d\n", $number);
}

codepad here http://codepad.org/a3Bl4TeA

edited Mar 16 '12 at 12:00

answered Mar 16 '12 at 11:52

Nicola Peluchetti

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score 0 · Answer 4 · answered Feb 20 '14 at 14:04

I have prefer to make my own scalable function to any other length you would like to use. here for example

function format3($number){
   if($number>99){$number=$number;}
     else{ if($number>9){$number="0".$number;} 
      else{$number="00".$number;
         }
     }
  return $number;
}

just call format3(/your value/) to see your value displaid in three digit $value=3 echo format3($value) //display 003 You can extend the function for longest patterns formatX()

php format a number so that it has leading zero

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