Blog Post Add Image Size Wp

the_post_thumbnail(); // Without parameter ->; Thumbnail
the_post_thumbnail( 'thumbnail' ); // Thumbnail (default 150px x 150px max)
the_post_thumbnail( 'medium' ); // Medium resolution (default 300px x 300px max)
the_post_thumbnail( 'medium_large' ); // Medium-large resolution (default 768px x no height limit max)
the_post_thumbnail( 'large' ); // Large resolution (default 1024px x 1024px max)
the_post_thumbnail( 'full' ); // Original image resolution (unmodified)
the_post_thumbnail( array( 100, 100 ) ); // Other resolutions (height, width)


add_image_size( 'category-thumb', 300, 9999 ); // 300 pixels wide (and unlimited height)


**-- create custom Featured Image sizes in your theme’s functions.php file. **

if ( function_exists( 'add_theme_support' ) ) {
    add_theme_support( 'post-thumbnails' );
    set_post_thumbnail_size( 150, 150, true ); // default Featured Image dimensions (cropped)
 
    // additional image sizes
    // delete the next line if you do not need additional image sizes
    add_image_size( 'category-thumb', 300, 9999 ); // 300 pixels wide (and unlimited height)
    
    
Styling Featured Images #Styling Featured Images
Featured Images are given a class “wp-post-image”.
They also get a class depending on the size of the thumbnail being displayed.
You can style the output with these CSS selectors:

img.wp-post-image
img.attachment-thumbnail
img.attachment-medium
img.attachment-large
img.attachment-full

Display the Featured Image with a class “alignleft”:
the_post_thumbnail( 'thumbnail', array( 'class' => 'alignleft' ) );

To link Post Thumbnails to the Post Permalink in a specific loop, 
use the following within your Theme’s template files:
<?php if ( has_post_thumbnail()) : ?>
   <a href="<?php the_permalink(); ?>" title="<?php the_title_attribute(); ?>" >
   <?php the_post_thumbnail(); ?>
   </a>
 <?php endif; ?>
 
 To link all Post Thumbnails on your website to the Post Permalink, 
 put this in the current Theme’s functions.php file:

add_filter( 'post_thumbnail_html', 'my_post_image_html', 10, 3 );
 
function my_post_image_html( $html, $post_id, $post_image_id ) {
 
  $html = '<a href="' . get_permalink( $post_id ) . '" title="' . esc_attr( get_the_title( $post_id ) ) . '">' . $html . '</a>';
  return $html;
 
}