---
layout: page
title: "JavaScript str_pad function"
comments: true
sharing: true
footer: true
alias:
- /functions/view/str_pad:525
- /functions/view/str_pad
- /functions/view/525
- /functions/str_pad:525
- /functions/525
---
<!-- Generated by Rakefile:build -->
A JavaScript equivalent of PHP's str_pad

{% codeblock strings/str_pad.js lang:js https://raw.github.com/kvz/phpjs/master/functions/strings/str_pad.js raw on github %}
function str_pad (input, pad_length, pad_string, pad_type) {
  // From: http://phpjs.org/functions
  // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  // + namespaced by: Michael White (http://getsprink.com)
  // +      input by: Marco van Oort
  // +   bugfixed by: Brett Zamir (http://brett-zamir.me)
  // *     example 1: str_pad('Kevin van Zonneveld', 30, '-=', 'STR_PAD_LEFT');
  // *     returns 1: '-=-=-=-=-=-Kevin van Zonneveld'
  // *     example 2: str_pad('Kevin van Zonneveld', 30, '-', 'STR_PAD_BOTH');
  // *     returns 2: '------Kevin van Zonneveld-----'
  var half = '',
    pad_to_go;

  var str_pad_repeater = function (s, len) {
    var collect = '',
      i;

    while (collect.length < len) {
      collect += s;
    }
    collect = collect.substr(0, len);

    return collect;
  };

  input += '';
  pad_string = pad_string !== undefined ? pad_string : ' ';

  if (pad_type !== 'STR_PAD_LEFT' && pad_type !== 'STR_PAD_RIGHT' && pad_type !== 'STR_PAD_BOTH') {
    pad_type = 'STR_PAD_RIGHT';
  }
  if ((pad_to_go = pad_length - input.length) > 0) {
    if (pad_type === 'STR_PAD_LEFT') {
      input = str_pad_repeater(pad_string, pad_to_go) + input;
    } else if (pad_type === 'STR_PAD_RIGHT') {
      input = input + str_pad_repeater(pad_string, pad_to_go);
    } else if (pad_type === 'STR_PAD_BOTH') {
      half = str_pad_repeater(pad_string, Math.ceil(pad_to_go / 2));
      input = half + input + half;
      input = input.substr(0, pad_length);
    }
  }

  return input;
}
{% endcodeblock %}

 - [Raw function on GitHub](https://github.com/kvz/phpjs/blob/master/functions/strings/str_pad.js)

Please note that php.js uses JavaScript objects as substitutes for PHP arrays, they are 
the closest match to this hashtable-like data structure. 

Please also note that php.js offers community built functions and goes by the 
[McDonald's Theory](https://medium.com/what-i-learned-building/9216e1c9da7d). We'll put online 
functions that are far from perfect, in the hopes to spark better contributions. 
Do you have one? Then please just: 

 - [Edit on GitHub](https://github.com/kvz/phpjs/edit/master/functions/strings/str_pad.js)

### Example 1
This code
{% codeblock lang:js example %}
str_pad('Kevin van Zonneveld', 30, '-=', 'STR_PAD_LEFT');
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
'-=-=-=-=-=-Kevin van Zonneveld'
{% endcodeblock %}

### Example 2
This code
{% codeblock lang:js example %}
str_pad('Kevin van Zonneveld', 30, '-', 'STR_PAD_BOTH');
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
'------Kevin van Zonneveld-----'
{% endcodeblock %}


### Other PHP functions in the strings extension
{% render_partial _includes/custom/strings.html %}