Create WordPress Thumbnail Without Custom Field

[thebestsolver.com] How to create thumbnail image post in wordpress ? there are many ways to make thumbnail post image in wordpress, but the discussion this time I will present how to create auto thumbnail wordpress without custom field !

1. Get the TimThumb.php Script
   Download timthumb.php script and upload in your theme
2. Edit Functions.php
   Open your theme’s functions.php file and copy paste the code below into it.

<?php
// retreives image from the post
function getImage($num) {
global $more;
$more = 1;
$content = get_the_content();
$count = substr_count($content, '<img');
$start = 0;
for($i=1;$i<=$count;$i++) {
$imgBeg = strpos($content, '<img', $start);
$post = substr($content, $imgBeg);
$imgEnd = strpos($post, '>');
$postOutput = substr($post, 0, $imgEnd+1);
$image[$i] = $postOutput;
$start=$imgEnd+1;

$cleanF = strpos($image[$num],'src="')+5;
$cleanB = strpos($image[$num],'"',$cleanF)-$cleanF;
$imgThumb = substr($image[$num],$cleanF,$cleanB);

}
if(stristr($image[$num],'<img')) { echo $imgThumb; }
$more = 0;
}
//retreive image ends
?>

3. Open main index.php your theme and insert the code to call the code, in this tutorial we’ll paste this code above the_excerpt(); or the_content(); in index.php or home.php file.
   

   <div>
   <a href="<?php the_permalink(); ?>" title="<?php the_title_attribute(); ?>">
   <img src="<?php bloginfo('template_directory'); ?>/timthumb.php?src=<?php getImage('1'); ?>&w=150&h=150&zc=1">
   </a>
   </div>

4. Add some CSS Rules
   You can style the thumbnail in any way you like, for example, you might add the following to your style.css file:

   .thumbnail a:link, .thumbnail a:visited {display:block; float:left; padding:5px; background:#e2e2e2; width:150px; height:150px; margin:5px 5px 0 0;}
   .thumbnail a:hover, .thumbnail a:active {background:#C4C4C4;}