Get current post id outside the loop. Wordpress - php

Question

I am making a plugin for wordpress. And the problem is that, how can I get the current post ID outside the loop?
I have a button on the post, and the post ID should be returned when the button is clicked by the user.
So, do anyway to get the post id?
My plugin dir: wp-content\plugins\updateDatabase\js\connectionDatabase.php
Here is my code: And my url http://localhost:8080/wordpress/?p=1169
$post_id = $_GET['p'];
echo $post_id;
$link = getConnection();
$bonusPoint = 0;
$query_sql = "SELECT bonus_point FROM post_data03 WHERE post_id =" .$post_id;
$result = mysqli_query($link, $query_sql);
if (mysqli_num_rows($result) > 0) {
// output data of each row
while($row = mysqli_fetch_assoc($result)) {
$bonusPoint = $row['bonus_point'];
}
} else {
echo "0 results";
}
Using $post:
function getBonusPointFromDataPost()
{
global $wp_query;
global $post;
$post_id = add_action( 'the_post', 'get_post_info' );
$link = getConnection();
}
GetBonusPointFromDataPost() will be fired when the user clicks the button which on the post page. And at the same time, the $post_id should be returned.
And I make a function to return the $post_id, but it only work when I add the action to it.
function get_post_info() {
global $wp_query;
global $post;
$post_id = $wp_query->post->ID;
echo $post_id;
return $post_id;
}
How can I return the $post_id when the user clicks the button.

Answer 1

Here it is,
use global $post to get the current post object
global $post;
echo $post->ID;