How to add extra field in add articles page?

Hi,

I want to add new field in add articles in admin. Can anyone let me know how I can add that.

Thanks in advance.

The array which describes article add form is located in the beginning of inc/classes/BxDolTextData.php file:

        $this->_aForm = array(
            'form_attrs' => array(
                'id' => 'text_data',
                'name' => 'text_data',
                'action' => bx_html_attribute($_SERVER['PHP_SELF']),
                'method' => 'post',
                'enctype' => 'multipart/form-data'
            ),
            'params' => array (
                'db' => array(
                    'table' => '',
                    'key' => 'id',
                    'uri' => 'uri',
                    'uri_title' => 'caption',
                    'submit_name' => 'post'
                ),
            ),
            'inputs' => array (
                'author_id' => array(
                    'type' => 'hidden',
                    'name' => 'author_id',
                    'value' => $this->_iOwnerId,
                    'db' => array (
                        'pass' => 'Int',
                    ),
                ),
                'caption' => array(
                    'type' => 'text',
                    'name' => 'caption',
                    'caption' => _t("_td_caption"),
                    'value' => '',
                    'required' => 1,
                    'checker' => array (
                        'func' => 'length',
                        'params' => array(3,64),
                        'error' => _t('_td_err_incorrect_length'),
                    ),
                    'db' => array (
                        'pass' => 'Xss',
                    ),
                ),
                'snippet' => array(
                    'type' => 'textarea',
                    'html' => 0,
                    'name' => 'snippet',
                    'caption' => _t("_td_snippet"),
                    'value' => '',
                    'required' => 1,
                    'checker' => array (
                        'func' => 'length',
                        'params' => array(3,200),
                        'error' => _t('_td_err_incorrect_length'),
                    ),
                    'db' => array (
                        'pass' => 'Xss',
                    ),
                ),
                'content' => array(
                    'type' => 'textarea',
                    'html' => 2,
                    'name' => 'content',
                    'caption' => _t("_td_content"),
                    'value' => '',
                    'required' => 1,
                    'checker' => array (
                        'func' => 'length',
                        'params' => array(3,65536),
                        'error' => _t('_td_err_incorrect_length'),
                    ),
                    'db' => array (
                        'pass' => 'XssHtml',
                    ),
                ),
                'when' => array(
                    'type' => 'datetime',
                    'name' => 'when',
                    'caption' => _t("_td_date"),
                    'value' => date('Y-m-d H:i'),
                    'required' => 1,
                    'checker' => array (
                        'func' => 'DateTime',
                        'error' => _t('_td_err_empty_value'),
                    ),
                    'db' => array (
                        'pass' => 'DateTime',
                    ),
                ),
                'tags' => array(
                    'type' => 'text',
                    'name' => 'tags',
                    'caption' => _t("_td_tags"),
                    'value' => '',
                    'required' => 1,
                    'checker' => array (
                        'func' => 'length',
                        'params' => array(3,64),
                        'error' => _t('_td_err_incorrect_length'),
                    ),
                    'info' => _t('_sys_tags_note'),
                    'db' => array (
                        'pass' => 'Xss',
                    ),
                ),
                'categories' => $oCategories->getGroupChooser($this->_oModule->_oConfig->getCategoriesSystemName(), $this->_iOwnerId, true),
                'allow_comment_to' => array(),
                'allow_vote_to' => array(),
                'post' => array(
                    'type' => 'submit',
                    'name' => 'post',
                    'value' => _t("_td_post"),
                ),
            )
        );

but do not touch this array - or different modules will be affected, it;s better make appropriate changes in modules/boonex/articles/classes/BxArlData.php file.