Best Collection of Code for your functions.php file [closed]

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As with many others who are now viewing this post, I have been reading various blogs, forums, and discussion groups to learn and improve my wordpress skills. Over the past 12 months I have been on a mission to substitute my use of plugins by adding code to my functions.phpfile instead. While I completely agree that plugins are very useful in many situations my experience proved that in 90% of usage cases although a plugin might exist, actually utilizing it could create unnecessary complications and compatibility issues. Additionally in a great deal of cases such plugins added menus and other admin elements which I don't want or need.

More often than not I have found that by analyzing the code of plugins I was able to strip out the piece of code I wanted and hard code it into my functions.php. This provided me with the exact functionality I needed without having to include unnecessary elements.

So, the purpose of this post is my attempt to engage you, the reader/admin/developer, to share with me and other here any code bits which you find useful and have added to your theme'sfunction.php file to extend or enhance WordPress without utilizing a plugin.

When you submit a response here please kindly give each code bit a title, let us know if with what version of wordpress you know its compatible with, include whatever description you feel best describes its function and (if applicable) include a link to the original plugin or source where you found the information.

I am looking forward to all your responses and will of course continually add my own new finds whenever I find them.

plugins functions customization admin pluggable

ANSWER:-

Tested on: WordPress 3.0.1

This code will allow you to easily modify the WordPress Login page Logo as well as the href link and title text of this logo.

add_filter( 'login_headerurl', 'namespace_login_headerurl' );
/**
 * Replaces the login header logo URL
 *
 * @param $url
 */
function namespace_login_headerurl( $url ) {
    $url = home_url( '/' );
    return $url;
}

add_filter( 'login_headertitle', 'namespace_login_headertitle' );
/**
 * Replaces the login header logo title
 *
 * @param $title
 */
function namespace_login_headertitle( $title ) {
    $title = get_bloginfo( 'name' );
    return $title;
}

add_action( 'login_head', 'namespace_login_style' );
/**
 * Replaces the login header logo
 */
function namespace_login_style() {
    echo '<style>.login h1 a { background-image: url( ' . get_template_directory_uri() . '/images/logo.png ) !important; }</style>';
}

EDIT: If you want to use the site logo to replace the login logo, you can use the following to dynamically pull that information (tested on WP3.5):

function namespace_login_style() {
    if( function_exists('get_custom_header') ){
        $width = get_custom_header()->width;
        $height = get_custom_header()->height;
    } else {
        $width = HEADER_IMAGE_WIDTH;
        $height = HEADER_IMAGE_HEIGHT;
    }
    echo '<style>'.PHP_EOL;
    echo '.login h1 a {'.PHP_EOL; 
    echo '  background-image: url( '; header_image(); echo ' ) !important; '.PHP_EOL;
    echo '  width: '.$width.'px !important;'.PHP_EOL;
    echo '  height: '.$height.'px !important;'.PHP_EOL;
    echo '  background-size: '.$width.'px '.$height.'px !important;'.PHP_EOL;
    echo '}'.PHP_EOL;
    echo '</style>'.PHP_EOL;
}

Posted in: WORDPRESS