php - codeigniter form validation for checkbox at least one selection -

php - codeigniter form validation for checkbox at least one selection -

i know how create form validation each of inputs in codeigniter. possible create validation multiple checkbox user should select @ to the lowest degree 1 check box?

example

<input type=checkbox name=days[] >mon <input type=checkbox name=days[] >tues <input type=checkbox name=days[] >wed <input type=checkbox name=days[] >thur

where codeigniter should validate user should select @ to the lowest degree 1 checkbox.?

html:

<input type=checkbox name=days[] >mon <input type=checkbox name=days[] >tues <input type=checkbox name=days[] >wed <input type=checkbox name=days[] >thur

use next code validate above html :

$this->form_validation->set_rules('days[]', 'days', 'required');

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