---
layout: page
title: "JavaScript constant function"
comments: true
sharing: true
footer: true
alias:
- /functions/view/constant:372
- /functions/view/constant
- /functions/view/372
- /functions/constant:372
- /functions/372
---
<!-- Generated by Rakefile:build -->
A JavaScript equivalent of PHP's constant

{% codeblock misc/constant.js lang:js https://raw.github.com/kvz/phpjs/master/functions/misc/constant.js raw on github %}
function constant (name) {
  // http://kevin.vanzonneveld.net
  // +   original by: Paulo Freitas
  // +   improved by: Brett Zamir (http://brett-zamir.me)
  // *     example 1: constant('IMAGINARY_CONSTANT1');
  // *     returns 1: null
  var clssPos = 0,
    clssCnst = null;
  if ((clssPos = name.indexOf('::')) !== -1) {
    clssCnst = name.slice(clssPos + 2);
    name = name.slice(0, clssPos);
  }

  if (this.window[name] === undefined) {
    return null;
  }
  if (clssCnst) {
    return this.window[name][clssCnst];
  }
  return this.window[name];
}
{% endcodeblock %}

 - [view on github](https://github.com/kvz/phpjs/blob/master/functions/misc/constant.js)
 - [edit on github](https://github.com/kvz/phpjs/edit/master/functions/misc/constant.js)

### Example 1
This code
{% codeblock lang:js example %}
constant('IMAGINARY_CONSTANT1');
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
null
{% endcodeblock %}


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