This ReactJS mixin adds component methods letting you generate unique IDs for your current component. This is useful when you need to assign for="" attributes for labels and their respective inputs.

npm install unique-id-mixin --save-dev

var UniqeIdMixin = require('unique-id-mixin');

var Component = React.createClass({
    mixins: [ UniqeIdMixin ],

    render: function() {
        return (
            <div>
                <label htmlFor={ this.getNextUid( 'unique-string' ) }>Label</label>
                <input id={ this.getNextUid( 'unique-string' ) } type="text" />
            </div>
        );
    }
});

The above can be a bit verbose to type, and has the problem that you need to duplicate the string between each HTML element. There is also a convenience method that will generate UIDs every other call. The first two calls will return the same UID, then the next two calls will return a new UID, etc.

<!-- Both function calls return the same UID -->
<label htmlFor={ this.getNextHtmlFor() }>Label</label>
<input id={ this.getNextHtmlFor() } type="text" />

<!-- Both calls now return the same UID, but different than above -->
<label htmlFor={ this.getNextHtmlFor() }>Label</label>
<input id={ this.getNextHtmlFor() } type="text" />

this.getNextUid( identifier:String )

Returns a UID generated using the identifier. If identifier has already been passed, the cached UID will be returned.

this.getNextHtmlFor()

Returns a UID which changes every other call.