If you want to add something to the <title>, without adding to the blog title, you can directly change that with a few lines of code:
add_filter( 'wp_title', 'append_to_title', 10, 3 );
function append_to_title( $title, $sep, $seplocation ) {
return $title .= "OMGBBQFTW $sep ";
}
If you want to change the output of anything the get_bloginfo() returns, there’s a couple of filters that make it simple:
(I’m going to leave the practical application brainstorming up to you)
For text:
add_filter( 'bloginfo', 'be_excited', 10, 2 );
function be_excited( $output, $show ) {
if ( 'name' == $show )
$output .= ' OMG BBQ!!! FTW';
return $output;
}
For URLs: change the filter hook to bloginfo_url
Very similar to a previous post about the “Log In” links, but for the “Register” link. If you think your users would be more comfortable with different verbiage, then make your users comfortable:
add_filter( 'register', 'reg2sign' );
function reg2sign( $link ) {
$link = str_replace( '>Register<', '>Sign Up<', $link );
return $link;
}
Relevant for WordPress 4.4: https://core.trac.wordpress.org/ticket/35103
If you’ve created a login page that isn’t at /wp-login.php, here’s a simple way you can redirect users who click on the “Log In” links to your new page:
add_filter( 'login_url', 'new_login_url', 10, 2 );
function new_login_url( $login_url, $redirect ) {
return '/log-in/';
}
If you’re using the handy wp_login_form() function to create a custom log in page, you may have noticed that you don’t get the “Lost Password?” link. Doesn’t take much to add it back:
add_action( 'login_form_middle', 'add_lost_password_link' );
function add_lost_password_link() {
return '<a href="/wp-login.php?action=lostpassword">Lost Password?</a>';
}
If you’d prefer your Log In/Out links use different verbiage, fear not! You can change it:
add_filter( 'loginout', 'log2sign' );
function log2sign( $link ) {
$link = str_replace( 'Log ', 'Sign ', $link );
return $link;
}
This is probably more practical if you deal with a lot of special characters, perhaps in foreign languages. But if you want to make sure particular characters are removed from file name when uploaded, you can. As always, WordPress makes this easy.
add_filter( 'sanitize_file_name_chars', 'add_chars_to_filter', 10, 2 );
function add_chars_to_filter ( $special_chars, $filename_raw ) {
$special_chars[] = 'e';
return $special_chars;
}
This particular is example is useless as-is, unless you have something against our favorite vowel ‘e.’
Did you know that WordPress will create a robots.txt file for you – well, sorta…
If you don’t create an actual robots.txt file, WordPress will create a virtual one for you, meaning that if yoursite.com/robots.txt is requested, WordPress will serve up robots.txt page, even though it doesn’t actually exist on your server.
Now that we’ve got that covered. How can you edit your virtual robots file? Easy
add_filter( 'robots_txt', 'robots_mod', 10, 2 );
function robots_mod( $output, $public ) {
$output .= "Disallow: /topsecret/\n";
return $output;
}If you want to make is it so that a user doesn’t know why a failed login failed, you can use these 2 lines of code. Useful if you’re the only user and you don’t want to give potential hackers any extra info. For example, if you have the right username but a bad password, by default it will tell you in the error message – letting the person know they have half the info correct. If a username doesn’t exist, that information is also revealed.
add_filter( 'login_errors', '__return_false' ); add_filter( 'login_messages', '__return_false' );
You might want to add a little CSS to make sure the empty error/message boxes don’t show up either:
add_action( 'login_head', 'login_head_css' );
function login_head_css() {
?><style type="text/css">.message, #login_error { display:none; }</style><?php
}
If you’re running a private blog and you want to make sure all logged-out visitors are redirected to the sign-in page, this will do the trick.
add_action( 'template_redirect', 'logged_in_users_only' );
function logged_in_users_only() {
if ( !is_user_logged_in() )
wp_redirect( wp_login_url() );
}
If you want users to come back to the front page after logging in, you can pass an argument to the wp_login_url() function.
add_action( 'template_redirect', 'logged_in_users_only' );
function logged_in_users_only() {
if ( !is_user_logged_in() )
wp_redirect( wp_login_url( home_url() ) );
}
This will only redirect users who were initially redirected to the login screen from the front-end. If the user went directly to the login screen – the filter above won’t have been triggered, so they’ll be taken to the administration side.