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| <h1>Array Helper</h1> |
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| <p>The Array Helper file contains functions that assist in working with arrays.</p> |
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| <h2>Loading this Helper</h2> |
| |
| <p>This helper is loaded using the following code:</p> |
| <code>$this->load->helper('array');</code> |
| |
| <p>The following functions are available:</p> |
| |
| <h2>element()</h2> |
| |
| <p>Lets you fetch an item from an array. The function tests whether the array index is set and whether it has a value. If |
| a value exists it is returned. If a value does not exist it returns FALSE, or whatever you've specified as the default value via the third parameter. Example:</p> |
| |
| <code> |
| $array = array('color' => 'red', 'shape' => 'round', 'size' => '');<br /> |
| <br /> |
| // returns "red"<br /> |
| echo element('color', $array);<br /> |
| <br /> |
| // returns NULL<br /> |
| echo element('size', $array, NULL); |
| </code> |
| |
| |
| <h2>random_element()</h2> |
| |
| <p>Takes an array as input and returns a random element from it. Usage example:</p> |
| |
| <code>$quotes = array(<br /> |
| "I find that the harder I work, the more luck I seem to have. - Thomas Jefferson",<br /> |
| "Don't stay in bed, unless you can make money in bed. - George Burns",<br /> |
| "We didn't lose the game; we just ran out of time. - Vince Lombardi",<br /> |
| "If everything seems under control, you're not going fast enough. - Mario Andretti",<br /> |
| "Reality is merely an illusion, albeit a very persistent one. - Albert Einstein",<br /> |
| "Chance favors the prepared mind - Louis Pasteur"<br /> |
| );<br /> |
| <br /> |
| echo random_element($quotes);</code> |
| |
| |
| <h2>elements()</h2> |
| |
| <p>Lets you fetch a number of items from an array. The function tests whether each of the array indices is set. If an index does not exist |
| it is set to FALSE, or whatever you've specified as the default value via the third parameter. Example:</p> |
| |
| <code> |
| $array = array(<br /> |
| 'color' => 'red',<br /> |
| 'shape' => 'round',<br /> |
| 'radius' => '10',<br /> |
| 'diameter' => '20'<br /> |
| );<br /> |
| <br /> |
| $my_shape = elements(array('color', 'shape', 'height'), $array);<br /> |
| </code> |
| |
| <p>The above will return the following array:</p> |
| |
| <code> |
| array(<br /> |
| 'color' => 'red',<br /> |
| 'shape' => 'round',<br /> |
| 'height' => FALSE<br /> |
| ); |
| </code> |
| |
| <p>You can set the third parameter to any default value you like:</p> |
| |
| <code> |
| $my_shape = elements(array('color', 'shape', 'height'), $array, NULL);<br /> |
| </code> |
| |
| <p>The above will return the following array:</p> |
| |
| <code> |
| array(<br /> |
| 'color' => 'red',<br /> |
| 'shape' => 'round',<br /> |
| 'height' => NULL<br /> |
| ); |
| </code> |
| |
| <p>This is useful when sending the <kbd>$_POST</kbd> array to one of your Models. This prevents users from |
| sending additional POST data to be entered into your tables:</p> |
| |
| <code> |
| $this->load->model('post_model');<br /> |
| <br /> |
| $this->post_model->update(elements(array('id', 'title', 'content'), $_POST)); |
| </code> |
| |
| <p>This ensures that only the id, title and content fields are sent to be updated.</p> |
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