PHP in a Nutshell

Name

str_pad()

Synopsis

    string str_pad ( string input, int length [, string padding [, int type]] )

The str_pad() function makes a given string (parameter one) larger by X number of characters (parameter two) by adding on spaces. For example:

    $string = "Goodbye, Perl!";
    $newstring = str_pad($string, 2);

That code would leave " Goodbye, Perl! " in $newstring, which is the same string from $string, except with a space on either side, equalling the two we passed in as parameter two.

There is an optional third parameter to str_pad() that lets you set the padding character to use, so:

    $string = "Goodbye, Perl!";
    $newstring = str_pad($string, 10, 'a');

That would put "aaaaaGoodbye, Perl!aaaaa" into $newstring.

We can extend the function even more by using its optional fourth parameter, which allows us to specify which side we want the padding added to. The fourth parameter is specified as a constant, and you either use STR_PAD_LEFT, STR_PAD_RIGHT, or STR_PAD_BOTH:

    $string = "Goodbye, Perl!";
    $a = str_pad($string, 10, '-', STR_PAD_LEFT);
    // $a is "----------Goodbye, Perl!"

    $b = str_pad($string, 10, '-', STR_PAD_RIGHT);
    // $b is "Goodbye, Perl!----------",

    $c = str_pad($string, 10, '-', STR_PAD_BOTH);
    // $c is "-----Goodbye, Perl!-----"

Note that HTML only allows a maximum of one space at any time. If you want to pad more, you will need to use &nbsp; the HTML code for a non-breaking space.