获取WordPress循环（loop）里的 key

Get current index position in loop in WordPress

获取当前元素的系列，只需要 $wp_query->current_post

while (have_posts()) : the_post();

// Some basic wordpress template tags
the_title();
the_content();

// Echo the current index position of the loop (0,1,2,3..etc)
echo $wp_query->current_post;

endwhile;

或者还有种原始的方法：

$key = "";
while (have_posts()) : the_post();

// Some basic wordpress template tags
the_title();
the_content();
echo $key;
$key++
endwhile;