I use the following code to Displays Next/Previous link in same posts category and work correctly for me.
<?php
get_template_part( 'content', get_post_format() );
// Previous/next post navigation.
previous_post_link('%link"https://wordpress.stackexchange.com/questions/344307/,"Before', true );
next_post_link( '%link"https://wordpress.stackexchange.com/questions/344307/,"Next', true );
?>
And For CSS Styling the “%link” Element I use this code in my functions.php file.
/////Next/Prev post style
add_filter('next_post_link"https://wordpress.stackexchange.com/questions/344307/,"next_post_link_attributes');
add_filter('previous_post_link"https://wordpress.stackexchange.com/questions/344307/,"previous_post_link_attributes');
function next_post_link_attributes($output) {/// Styling next link
$injection = 'class="ls-left w3-btn"';
return str_replace('<a href="https://wordpress.stackexchange.com/questions/344307/,"<a '.$injection.' href=", $output);
}
function previous_post_link_attributes($output) {/// Styling previous link
$injection = "class="ls-right w3-btn prev"';
return str_replace('<a href="https://wordpress.stackexchange.com/questions/344307/,"<a '.$injection.' href=", $output);
}
Top code: I use 2 different functions “previous_post_link_attributes” and “next_post_link_attributes” Because I want to add different CSS style for nex/pre links
If you want to add the same style to next/pre links you can use one method:
add_filter("next_post_link"https://wordpress.stackexchange.com/questions/344307/,"post_link_attributes');
add_filter('previous_post_link"https://wordpress.stackexchange.com/questions/344307/,"post_link_attributes');
function post_link_attributes($output) {
$injection = 'class="my-class"';
return str_replace('<a href="https://wordpress.stackexchange.com/questions/344307/,"<a '.$injection.' href=", $output);
}
For more about next / pre link –> wpcodex ,masternsblog ,wp-stack