Wordpress 儿童主题

Question

I'm trying to redeclare a function in a wordpress child theme that is already in use by the parent theme. However, I get a "Fatal error: Cannot redeclare" message when trying to do so.

Also, I've tried using the following with no luck:

if (!function_exists('jr_load_scripts')) {
  // do fancy things here...
}

Here's the link if you want to have a quick look...

EDIT: Here's the full code:

if (!function_exists('jr_load_scripts')) {
function jr_load_scripts() {
global $app_abbr;

$http = (is_ssl()) ? 'https' : 'http';

// load google cdn hosted scripts if enabled
if (get_option($app_abbr.'_google_jquery') == 'yes') :

    wp_deregister_script('jquery');
    wp_register_script('jquery', (''.$http.'://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js'), false, '1.4.2');
    wp_register_script('jquery-ui-custom', ''.$http.'://ajax.googleapis.com/ajax/libs/jqueryui/1.8/jquery-ui.min.js', false, '1.8');

else :

    wp_register_script('jquery-ui-custom', get_bloginfo('template_directory').'/includes/js/jquery-ui-1.8.custom.min.js', false, '1.8');

endif;

wp_enqueue_script('jquery');
wp_enqueue_script('jquery-ui-custom');

wp_enqueue_script('jquery-tag', get_bloginfo('template_directory').'/includes/js/jquery.tag.js', array('jquery'), '');
wp_enqueue_script('smoothscroll', get_bloginfo('template_directory').'/includes/js/smoothscroll.js', array('jquery'), '');
wp_enqueue_script('lazyload', get_bloginfo('template_directory').'/includes/js/jquery.lazyload.mini.js', array('jquery'), '1.5.0');
wp_enqueue_script('elastic', get_bloginfo('template_directory').'/includes/js/jquery.elastic.js', array('jquery'), '1.0');
wp_enqueue_script('fancybox', get_bloginfo('template_directory').'/includes/js/jquery.fancybox-1.3.4.pack.js', array('jquery'), '1.3.4');
wp_enqueue_script('qtip', get_bloginfo('template_directory').'/includes/js/jquery.qtip.min.js', array('jquery'), '1.0.0-rc3');
wp_enqueue_script('general', get_bloginfo('template_directory').'/includes/js/theme-scripts.js', array('jquery'), '3.0');

$jr_enable_indeed_feeds = get_option('jr_enable_indeed_feeds');
if ($jr_enable_indeed_feeds=='yes') :

     wp_enqueue_script('indeed-api', ''.$http.'://www.indeed.com/ads/apiresults.js');

wp_enqueue_script('jqtransform', get_bloginfo('template_directory') . '/includes/jqtransformplugin/jquery.jqtransform.js', array('jquery'),'');

endif;
}

EDIT2: As requested - the contents of the theme-enqueue file:

<?php
/**
 * These are scripts used within the JobRoller theme
 * To increase speed and performance, we only want to
 * load them when needed
 *
 * @package JobRoller
 * @version 1.0
 *
 */

function jr_load_scripts() {
    global $app_abbr;

    $http = (is_ssl()) ? 'https' : 'http';

    // load google cdn hosted scripts if enabled
    if (get_option($app_abbr.'_google_jquery') == 'yes') :

        wp_deregister_script('jquery');
        wp_register_script('jquery', (''.$http.'://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js'), false, '1.4.2');
        wp_register_script('jquery-ui-custom', ''.$http.'://ajax.googleapis.com/ajax/libs/jqueryui/1.8/jquery-ui.min.js', false, '1.8');

    else :

        wp_register_script('jquery-ui-custom', get_bloginfo('template_directory').'/includes/js/jquery-ui-1.8.custom.min.js', false, '1.8');

    endif;

    wp_enqueue_script('jquery');
    wp_enqueue_script('jquery-ui-custom');

    wp_enqueue_script('jquery-tag', get_bloginfo('template_directory').'/includes/js/jquery.tag.js', array('jquery'), '');
    wp_enqueue_script('smoothscroll', get_bloginfo('template_directory').'/includes/js/smoothscroll.js', array('jquery'), '');
    wp_enqueue_script('lazyload', get_bloginfo('template_directory').'/includes/js/jquery.lazyload.mini.js', array('jquery'), '1.5.0');
    wp_enqueue_script('elastic', get_bloginfo('template_directory').'/includes/js/jquery.elastic.js', array('jquery'), '1.0');
    wp_enqueue_script('fancybox', get_bloginfo('template_directory').'/includes/js/jquery.fancybox-1.3.4.pack.js', array('jquery'), '1.3.4');
    wp_enqueue_script('qtip', get_bloginfo('template_directory').'/includes/js/jquery.qtip.min.js', array('jquery'), '1.0.0-rc3');
    wp_enqueue_script('general', get_bloginfo('template_directory').'/includes/js/theme-scripts.js', array('jquery'), '3.0');

    $jr_enable_indeed_feeds = get_option('jr_enable_indeed_feeds');
    if ($jr_enable_indeed_feeds=='yes') :

         wp_enqueue_script('indeed-api', ''.$http.'://www.indeed.com/ads/apiresults.js');

    endif;
}

// this function is called when submitting a new job listing
function jr_load_form_scripts() {
    // only load the tinymce editor when html is allowed
    if (get_option('jr_html_allowed') == 'yes') {
        wp_enqueue_script('tiny_mce', get_bloginfo('url').'/wp-includes/js/tinymce/tiny_mce.js');
        wp_enqueue_script('tiny_mce-wp-langs-en', get_bloginfo('url').'/wp-includes/js/tinymce/langs/wp-langs-en.js');
    }
}

// to speed things up, don't load these scripts in the WP back-end (which is the default)
if(!is_admin()) {
    add_action('wp_print_scripts', 'jr_load_scripts');
    // add_action('wp_print_styles', 'cp_load_styles');
}

Answer 1

You cannot override that function, as the parent theme's declaration is executed after your declaration, and it doesn't try to check if the function already exists.

The only way would be to wrap the parent theme's function declaration inside the if condition.

if (!function_exists('jr_load_scripts')) {

}